Seattle Code (1972)

INTERNATIONAL CODE OF BOTANICAL NOMENCLATURE

PREAMBLE

Botany requires a precise and simple system of nomenclature used by botanists
in all countries, dealing on the one hand with the terms which denote the ranks of
taxonomic groups or units, and on the other hand with the scientific names which
are applied to the individual taxonomic groups of plants. The purpose of giving a
name to a taxonomic group is not to indicate its characters or history, but to supply
a means of referring to it and to indicate its taxonomic rank. This Code aims at
the provision of a stable method of naming taxonomic groups, avoiding and rejecting
the use of names which may cause error or ambiguity or throw science into con-
fusion. Next in importance is the avoidance of the useless creation of names. Other
considerations, such as absolute grammatical correctness, regularity or euphony of
names, more or less prevailing custom, regard for persons, etc., notwithstanding
their undeniable importance, are relatively accessory.

The Principles form the basis of the system of botanical nomenclature.

The detailed provisions are divided into Rules, set out in the Articles, and Recom-
mendations; the notes attached to these are integral parts of them. Examples are
added to the rules and recommendations to illustrate them.

The object of the Rules is to put the nomenclature of the past into order and to
provide for that of the future; names contrary to a rule cannot be maintained.

The Recommendations deal with subsidiary points, their object being to bring
about greater uniformity and clearness, especially in future nomenclature; names
contrary to a recommendation cannot, on that account, be rejected, but they are
not examples to be followed.

The provisions regulating the modification of this Code form its last division.

The Rules and Recommendations apply throughout the plant kingdom, recent
and fossil. However, special provisions are needed for certain groups. The Inter-
national Committee on Nomenclature of Bacteria has therefore issued an International
Code of Nomenclature of Bacteria (Internat. Journ. Syst. Bact. 16: 459-490. 1966).
Similarly the International Commission for the Nomenclature of Cultivated Plants has
published an International Code of Nomenclature of Cultivated Plants (Reg. Veg. 64.
1969). Provisions for the names of hybrids appear in Appendix I.

The only proper reasons for changing a name are either a more profound
knowledge of the facts resulting from adequate taxonomic study or the necessity of
giving up a nomenclature that is contrary to the rules.

In the absence of a relevant rule or where the consequences of rules are doubtful,
established custom is followed.

This edition of the Code supersedes all previous editions (see Bibliographia,
p. 394).

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Division I. Principles

Principle I

Botanical nomenclature is independent of zoological nomenclature.

The Code applies equally to names of taxonomic groups treated as plants whether
or not these groups were originally assigned to the plant kingdom.

Principle II

The application of names of taxonomic groups is determined by means of nomen-
clatural types.

Principle III

The nomenclature of a taxonomic group is based upon priority of publication.

Principle IV

Each taxonomic group with a particular circumscription, position, and rank can
bear only one correct name, the earliest that is in accordance with the Rules, except
in specified cases.

Principle V

Scientific names of taxonomic groups are treated as Latin regardless of their
derivation.

Principle VI

The Rules of nomenclature are retroactive unless expressly limited.

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Division I I. Rules and Recommendations

Chapter I. RANKS OF TAXA, AND THE TERMS DENOTING THEM

Article 1

Taxonomic groups of any rank will, in this Code, be referred to as taxa (singular:
taxon).

Article 2

Every individual plant is treated as belonging to a number of taxa of consecutively
subordinate ranks, among which the rank of species (species) is basal.

Article 3

The principal ranks of taxa in ascending sequence are: species (species), genus
(genus), family (familia), order (ordo), class (classis), and division (divisio). Thus
each species belongs (is to be assigned) to a genus, each genus to a family (certain
groups of fossil plants excepted), etc.

Note 1. Since the names of species, and consequently of many higher taxa, of
fossil plants are usually based on fragmentary specimens, and since the connection
between these specimens can only rarely be proved, organ-genera (organo-genera)
and form-genera (forma-genera) are distinguished as taxa within which species may
be recognized and given names according to this Code.

An organ-genus is a genus assignable to a family. A form-genus is a genus
unassignable to a family, but it may be referable to a taxon of higher rank (see
Art. 59). Form-genera are artificial in varying degree.

Examples: Organ-genera: Lepidocarpon Scott (Lepidocarpaceae), Mazocarpon (Scott) Benson
(Sigillariaceae), Siltaria Traverse (Fagaceae).

Form-genera: Dadoxylon Endl. (Coniferopsida), Pecopteris (Brongn.) Sternb. (Pteropsida),
Stigmaria Brongn. (Lepidophytales and Lepidospermales), Spermatites Miner (Cormophyta,
excl. Eocormophyta et Palaeocormophyta microphylla).

For the ranks of hybrid taxa, see Art. H. 1.

Article 4

If a greater number of ranks of taxa is required, the terms for these are made
either by adding the prefix sub (sub-) to the terms denoting the ranks or by the
introduction of supplementary terms. A plant may be assigned to taxa of the
following subordinate ranks of the plant kingdom (Regnum Vegetabile): Divisio,
Subdivisio, Classis, Subclassis, Ordo, Subordo, Familia, Subfamilia, Tribus, Sub-
tribus, Genus, Subgenus, Sectio, Subsectio, Series, Subseries, Species, Subspecies,
Varietas, Subvarietas, Forma, Subforma.

Further supplementary ranks may be intercalated or added, provided that con-
fusion or error is not thereby introduced.

For hybrids and certain variants of species in cultivation, see Appendix I and
Article 28.

Note. In classifying parasites, especially fungi, authors who do not give specific,
subspecific or varietal value to taxa characterized from a physiological standpoint
but scarcely or not at all from a morphological standpoint may distinguish within
the species special forms (formae speciales) characterized by their adaptation to
different hosts, but the nomenclature of formae speciales shall not be governed by
the provisions of this Code.

Article 5

The relative order of the ranks specified in Arts. 3 and 4 must not be altered.

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Chapter II. NAMES OF TAXA (GENERAL PROVISIONS)

Section 1. DEFINITIONS

Article 6

Effective publication is publication in accordance with Arts. 29—31.

Valid publication of names is publication in accordance with Arts. 32—45.

A legitimate name or epithet is one that is in accordance with the rules.

An illegitimate name or epithet is one that is contrary to the rules.

The correct name of a taxon with a particular circumscription, position, and rank
is the legitimate name which must be adopted for it under the rules (see Art. 11).

Example: The generic name Vexillifera Ducke (Arch. Jard. Bot. Rio de Janeiro 3: 139.
1922), based on the single species V. micranthera, is legitimate because it is in accordance
with the rules. The same is true of the generic name Dussia Krug et Urban ex Taub. (in
Engl. et Prantl, Nat. Pflanzenfam. III. 3: 193. 1892), based on the single species D. martini-
censis. Both generic names are correct when the genera are thought to be separate. Harms
(Repert. Sp. Nov. 19: 291. 1924), however, united Vexillifera Ducke and Dussia Krug et
Urban ex Taubert in a single genus; when this treatment is accepted the latter name is the
only correct one for the genus with this particular circumscription. The legitimate name
Vexillifera may therefore be correct or incorrect according to different concepts of the taxa.

Note 1. In this Code, unless otherwise indicated, the word “name” means
a name that has been validly published, whether it is legitimate or illegitimate.

Note 2. The name of a taxon below the rank of genus, consisting of the name
of a genus combined with one or more epithets, is termed a combination.

Examples of combinations: Gentiana lutea, Gentiana tenella var. occidentalis, Equisetum
palustre var. americanum f. fluitans, Mouriri subg. Pericrene, Arytera sect. Mischarytera.

Section 2. TYPIFICATION

Article 7

The application of names of taxa of the rank of family or below is determined

by means of nomenclatural types (types of names of taxa). A nomenclatural type
(typus) is that constituent element of a taxon to which the name of the taxon is
permanently attached, whether as a correct name or as a synonym.

Note 1. The nomenclatural type is not necessarily the most typical or represen-
tative element of a taxon; it is that element with which the name is permanently
associated.

A holotype is the one specimen or other element used by the author or designated
by him as the nomenclatural type. As long as a holotype is extant, it automatically
fixes the application of the name concerned.

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If no holotype was indicated by the author who described a taxon, or when the
holotype has been lost or destroyed, a lectotype or a neotype as a substitute for it
may be designated. A lectotype always takes precedence over a neotype. An isotype,
if such exists, must be chosen as the lectotype. If no isotype exists, the lectotype must
be chosen from among the syntypes, if such exist. If neither an isotype nor a syntype
nor any of the original material is extant, a neotype may be selected.

A lectotype is a specimen or other element selected from the original material to
serve as a nomenclatural type when no holotype was designated at the time of

publication or as long as it is missing. When two or more specimens have been
designated as types by the author of a specific or infra-specific name (e.g. male and
female, flowering and fruiting, etc.), the lectotype must be chosen from among them.

An isotype is any duplicate (part of a single gathering made by a collector at
one time) of the holotype; it is always a specimen.

A syntype is any one of two or more specimens cited by the author when no
holotype was designated, or any one of two or more specimens simultaneously
designated as types.

A neotype is a specimen or other element selected to serve as nomenclatural type
as long as all of the material on which the name of the taxon was based is missing.*

A new name or epithet published as an avowed substitute (nomen novum) for an
older name or epithet is typified by the type of the older name.

A new name formed from a previously published legitimate name or epithet (stat.
nov., comb. nov.) is, in all circumstances, typified by the type of the basionym.

A name or epithet which was nomenclaturally superfluous when published (see
Art. 63) is automatically typified by the type of the name or epithet which ought
to have been adopted under the rules, unless the author of the superfluous name
or epithet has indicated a definite type.

The type of a name of a taxon assigned to a group with a nomenclatural starting-
point later than 1753 (see Art. 13) is to be determined in accordance with the
indication or description and other matter accompanying its first valid publication

(see Arts. 32—45). When valid publication is by reference to a pre-starting-point
description, the latter must be used for purposes of typification as though newly
published.

A change of the listed type-species of a conserved generic name (see Art. 14 and
App. III) can be effected only by a procedure similar to that adopted for the con-
servation of generic names.

Example: Bullock and Killick (Taxon 6: 239. 1957) proposed, in the interests of stability
and taxonomic accuracy, that the type-species of Plectranthus L’Hér. should be changed from
P. punctatus (L.f.) L’Hér. to P. fruticosus L’Hér. This was approved by the appropriate
Committees and sanctioned by an International Botanical Congress.

The type of the name of a taxon of fossil plants of the rank of species or below is
the specimen whose figure accompanies or is cited in the valid publication of the
name (see Art. 38). If figures of more than one specimen were given or cited when
the name was validly published, one of those specimens must be chosen as type.

Note 2. The typification of names of genera based on plant megafossils and
plant microfossils (form- and organ-genera), genera of imperfect fungi, and any
other analogous genera or lower taxa does not differ from that indicated above.

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Recommendation 7A

It is strongly recommended that the material on which the name of a taxon is based,
especially the holotype, be deposited in a permanent, responsible institution and that it be
scrupulously conserved. When living material is designated as a nomenclatural type (for
Bacteria only; see Art. 9, paragraph 3), appropriate parts of it should be immediately preserved.

Recommendation 7B

Whenever the elements on which the name of a taxon is based are heterogeneous, the
lectotype should be so selected as to preserve current usage unless the element thus selected
is discordant with the protologue.*

Article 8

The author who first designates a lectotype or a neotype must be followed, but
his choice is superseded if the holotype or, in the case of a neotype, any of the
original material is rediscovered; it may also be superseded if it can be shown that
the choice was based upon a misinterpretation of the protologue, or was made
arbitrarily.

Example: In Britton & Brown’s Illustrated Flora (ed. 2. 1913), a type species was designated
for each genus. The lectotype, as understood by the authors, was “the first binomial species
in order” eligible under certain provisions. This is considered an arbitrary selection, as e.g.
the lectotypification of Delphinium L. (a genus assigned by its author to Polyandria Trigynia) by
D. consolida L. (a unicarpellate species).

Article 9

The type (holotype, lectotype, or neotype) of a name of a species or infraspecific
taxon is a single specimen or other element except in the following case: for small
herbaceous plants and for most non-vascular plants, the type may consist of more
than one individual, which ought to be conserved permanently on one herbarium
sheet or in one preparation.

If it is later proved that such a type herbarium sheet or preparation contains parts
belonging to more than one taxon, the name must remain attached to that part (lecto-
type) which corresponds most nearly with the original description.

Examples: The holotype of the name Rheedia kappleri Eyma, a polygamous species, is a
male specimen collected by Kappler (593a in U). The author designated a hermaphroditic
specimen collected by the Forestry Service of Surinam as a paratype ** (B. W. 1618 in U).

The type of the name Tillandsia bryoides Griseb. ex Baker (Journ. Bot. 16: 236. 1878) is
Lorentz no. 128 in BM; this, however, proved to be a mixture. L. B. Smith (Proc. Am. Acad.
70: 192. 1935) acted in accordance with this rule in designating one part of Lorentz’s gathering
as the lectotype.

Type specimens of names of taxa, the Bacteria excepted, must be preserved
permanently and cannot be living plants or cultures.

Note 1. If it is impossible to preserve a specimen as the type of a name of a

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* Protologue (from προθος, first, λογος, discourse): everything associated with a name at
its first publication, i.e. diagnosis, description, illustrations, references, synonymy, geographical
data, citation of specimens, discussion, and comments.

** See Guide for the determination of types (p. 75).

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species or infraspecific taxon of recent* plants, or if such a name is without a type
specimen, the type may be a description or figure.

Note 2. One whole specimen used in establishing a taxon of fossil plants is to
be considered the nomenclatural type. If this specimen is cut into pieces (sections
of fossil wood, pieces of coalball plants, etc.), all parts originally used in establishing
the diagnosis ought to be clearly marked.

Article 10

The type of a name of a genus or of any taxon between genus and species is a
species, that of a name of a family or of any taxon between family and genus is the
genus on whose present or former name that of the taxon concerned is based (see
also Art. 18).

The principle of typification does not apply to names of taxa above the rank of
family (see Art. 16).

Note 1. The type of a name of a family not based on a generic name is the genus
that typifies the alternative name of that family (see Art. 18).

Note 2. For the typification of some names of subdivisions of genera ** see
Art. 22.

Section 3. PRIORITY

Article 11

Each family or taxon of lower rank with a particular circumscription, position,
and rank can bear only one correct name, special exceptions being made for 9
families for which alternative names are permitted (see Art. 18) and for certain
fungi and fossil plants (see Art. 59).

For any taxon from family to genus inclusive, the correct name is the earliest
legitimate one with the same rank, except in cases of limitation of priority by
conservation (see Arts. 14 and 15) or where Arts. 13f, 58, or 59 apply.

For any taxon below the rank of genus, the correct name is the combination of
the earliest available legitimate epithet in the same rank with the correct name of
the genus or species to which it is assigned, except where Arts. 13f, 22, 26, 58, or
59 apply.

The principle of priority does not apply to names of taxa above the rank of family
(see Art. 16).

Article 12

A name of a taxon has no status under this Code unless it is validly published
(see Arts. 32–45).

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* The term recent as used here and elsewhere in the Code is in contradistinction to fossil
(see Art. 13, Note 2).

** Here and elsewhere in the Code the phrase “subdivision of a genus” refers only to taxa
between genus and species in rank.

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Section 4. LIMITATION OF THE PRINCIPLE OF PRIORITY

Article 13

Valid publication of names for plants of the different groups is treated as
beginning at the following dates (for each group a work is mentioned which is
treated as having been published on the date given for that group):

Recent plants

a. SPERMATOPHYTA and PTERIDOPHYTA, 1 May 1753 (Linnaeus, Species Plantarum
ed. 1).

b. MUSCI (the SPHAGNACEAE excepted), 1 Jan. 1801 (Hedwig, Species Muscorum).

c. SPHAGNACEAE and HEPATICAE, 1 May 1753 (Linnaeus, Species Plantarum ed. 1).

d.   LICHENES, 1 May 1753 (Linnaeus, Species Plantarum ed. 1). For nomenclatural
          purposes names given to lichens shall be considered as applying to their
          fungal components.

e. FUNGI: UREDINALES, USTILAGINALES and GASTEROMYCETES, 31 Dec. 1801 (Persoon,
Synopsis Methodica Fungorum).

f.   FUNGI CAETERI, 1 Jan. 1821 (Fries, Systema Mycologicum vol. 1). Vol. 1 of the
          Systema is treated as having appeared on 1 Jan. 1821, and the Elenchus
          Fungorum (1828) is treated as a part of the Systema. Names of FUNGI CAETERI
          published in other works between the dates of the first (vol. 1) and last (vol. 3,
          part 2 and index) part of the Systema which are synonyms or homonyms
          of names of any of the FUNGI CAETERI, included in the Systema do not affect
          the nomenclatural status of names used by Fries in this work.

g.   ALGAE, 1 May 1753 (Linnaeus, Species Plantarum ed. 1). Exceptions:
          NOSTOCACEAE HOMOCYSTEAE, 1892—93 (Gomont, Monographie des Oscillariées,
          Ann. Sci. Nat. Bot. VII. 15: 263—368; 16: 91—264).
          NOSTOCACEAE HETEROCYSTEAE, 1886—88 (Bornet et Flahault, Revision des
          Nostocacées hétérocystées, Ann. Sci. Nat. Bot. VII. 3: 323—381; 4: 343—373;
          5: 51—129; 7: 177—262).
          DESMIDIACEAE British Desmidieae).
          OEDOGONIACEAE, 1900 (Hirn, Monographie und Iconographie der Oedogonia-
          ceen, Acta Soc. Sci. Fenn. 27(1)).

h. MYXOMYCETES, 1 May 1753 (Linnaeus, Species Plantarum ed. 1).

i.    BACTERIA, 1 May 1753 (Linnaeus, Species Plantarum ed. 1). The names of
          bacteria are subject to provisions of the International Code of Nomenclature
          of Bacteria.

Fossil plants

j.    ALL GROUPS, 31 Dec. 1820 (Sternberg, Flora der Vorwelt, Versuch 1: 1—24.
          t. 1—13). Schlotheim, Petrefactenkunde, 1820, is regarded as published before
          31 Dec. 1820.

Note 1. The group to which a name is assigned for the purposes of this Article
is determined by the accepted taxonomic position of the type of the name.

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Examples: The genus Porella and its single species, P. pinnata, were referred by Linnaeus
(Sp. Pl. 2: 1106. 1753) to the Musci; if the type specimen of P. pinnata is accepted as
belonging to the Hepaticae, the names were validly published in 1753.

The lectotype species of Lycopodium L. (Sp. Pl. 2: 1100. 1753; Gen. Pl. ed. 5. 486. 1754)
is L. clavatum L. (Sp. Pl. 2: 1101. 1753) and the type specimen of this is currently accepted
as a pteridophyte. Accordingly, although the genus is listed by Linnaeus among the Musci,
the generic name and the names of the pteridophyte species included by Linnaeus under it
were validly published in 1753.

Note 2. Whether a name applies to a taxon of fossil plants or of recent plants
is decided by reference to the specimen that serves directly or indirectly as its
nomenclatural type. The name of a species or infraspecific taxon is treated as per-
taining to a recent taxon unless its type specimen is fossil in origin. Fossil material
is distinguished from recent material by stratigraphic relations at the site of original
occurrence. In cases of doubtful stratigraphic relations, regulations for recent taxa
shall apply.

Note 3. It is agreed to associate generic names which first appear in Linnaeus’
Species Plantarum ed. 1 (1753) and ed. 2 (1762—63) with the first subsequent
description given under those names in Linnaeus’ Genera Plantarum ed. 5 (1754)
and ed. 6 (1764) (see Art. 41).

Note 4. The two volumes of Linnaeus’ Species Plantarum ed. 1 (1753), which
appeared in May and August, 1753, respectively, are treated as having been published
simultaneously on the former date (1 May 1753).

Example: The generic names Thea L. Sp. Pl. 515 (May 1753) and Camellia L. Sp. Pl. 698
(Aug. 1753), Gen. Pl. ed. 5. 311 (1754) are treated as having been published simultaneously
in May 1753. Under Art. 57 the combined genus bears the name Camellia, since Sweet
(Hort. Suburb. Land. 157. 1818), who was the first to unite the two genera, chose that
name, citing Thea as a synonym.

Article 14

In order to avoid disadvantageous changes in the nomenclature of genera, families,
and intermediate taxa entailed by the strict application of the rules, and especially
of the principle of priority in starting from the dates given in Art. 13, this Code
provides, in Appendices II and III, lists of names that are conserved (nomina con-
servanda) and must be retained as useful exceptions. Conservation aims at retention
of those generic names which best serve stability of nomenclature. (See Rec. 50E.)

Note 1. These lists of conserved names will remain permanently open for addi-
tions. Any proposal of an additional name must be accompanied by a detailed
statement of the cases both for and against its conservation. Such proposals must
be submitted to the General Committee (see Division III), which will refer them
for examination to the committees for the various taxonomic groups.

Note 2. The application of both conserved and rejected names is determined
by nomenclatural types.

Note 3. A conserved name is conserved against all other names in the same rank
based on the same type (nomenclatural synonyms, which are to be rejected) whether
these are cited in the corresponding list of rejected names or not, and against those
names based on different types (taxonomic synonyms) that are cited in that list.

When a conserved name competes with one or more other names based on different
types and against which it is not explicitly conserved, the earliest of the competing
names is adopted in accordance with Art. 57.

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Examples: If the genus Weihea Spreng. (1825) is united with Cassipourea Aubl. (1775),
the combined genus will bear the prior name Cassipourea, although Weihea is conserved and
Cassipourea is not.

If Mahonia Nutt. (1818) is united with Berberis L. (1753), the combined genus will bear
the prior name Berberis, although Mahonia is conserved.

Nasturtium R. Br. (1812) was conserved only in the restricted sense, for a monotypic
genus based on N. officinale R. Br.; hence, if it is reunited with Rorippa Scop. (1760), it
must bear the name Rorippa.

Note 4. When a name of a genus has been conserved against an earlier name
based on a different type, the latter is to be restored, subject to Art. 11, if it is
considered the name of a genus distinct from that of the nomen conservandum except
when the earlier rejected name is a homonym of the conserved name.

Example: The generic name Luzuriaga Ruiz et Pav. (1802) is conserved against the earlier
names Enargea Banks et Sol. ex Gaertn. (1788) and Callixene Comm. ex Juss. (1789). If,
however, Enargea Banks et Sol. ex Gaertn. is considered to be a separate genus, the name
Enargea is retained for it.

Note 5. A conserved name is conserved against all its earlier homonyms.

Example: The generic name Smithia Ait. (1789), conserved against Damapana Adans., is
thereby conserved automatically against the earlier homonym Smithia Scop. (1777).

Note 6. Provision for the conservation of a name in a sense that excludes the
original type is made in Art. 48.

Note 7. When a name is conserved only to preserve a particular orthography,
it is to be attributed without change of priority to the author who originally
described the taxon.

Article 15

When a name proposed for conservation has been approved by the General
Committee after study by the Committee for the taxonomic group concerned, botanists
are authorized to retain it pending the decision of a later International Botanical
Congress.

Recommendation 15A

When a name proposed for conservation has been referred to the appropriate Committee
for study, botanists should follow existing usage as far as possible pending the General
Committee’s recommendation on the proposal.

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Chapter III. NOMENCLATURE OF TAXA ACCORDING TO THEIR RANK

Section 1. NAMES OF TAXA ABOVE THE RANK OF FAMILY

Article 16

The principles of priority and typification do not affect the form of names of
taxa above the rank of family. (See Arts. 10 and 11.)

Recommendation 16A

(a) The name of a division is preferably taken from characters indicating the nature of
the division as closely as possible; it should end in -phyta, except when it is a division of
FUNGI, in which case it should end in -mycota. Words of Greek origin are generally
preferable.

The name of a subdivision is formed in a similar manner; it is distinguished from a
divisional name by an appropriate prefix or suffix or by the ending -phytina, except when
it is a subdivision of FUNGI, in which case it should end in -mycotina.

(b) The name of a class or of a subclass is formed in a similar manner and should end
as follows:

1. In the ALGAE: -phyceae (class) and -phycidae (subclass);

2. In the FUNGI: -mycetes (class) and -mycetidae (subclass);

3. In the CORMOPHYTA: -opsida (class) and -idae (subclass).

Article 17

If the name of an order is based on the stem of a name of a family, it must have
the ending -ales. If the name of a suborder is based on the stem of a name of a
family, it must have the ending -ineae.

Note 1. Names intended as names of orders, but published with their rank
denoted by a term such as “Cohors”, “Nixus”, “Alliance”, or “Reihe” instead of
ordo are treated as having been published as names of orders.

Note 2. When the name of an order or suborder based on the stem of a name
of a family has been published with an improper termination, the ending is to be
changed to accord with the rule, without change of the author’s name.

Examples of names of orders: Fucales, Polygonales, Centrospermae, Parietales, Farinosae,
Ustilaginales; suborders: Enantioblastae, Bromeliineae, Malvineae.

Recommendation 17A

Authors should not publish new names of orders for taxa of that rank which include a
family from whose name an existing ordinal name is derived.

Section 2. NAMES OF FAMILIES AND SUBFAMILIES,

TRIBES AND SUBTRIBES

Article 18

The name of a family is a plural adjective used as a substantive; it is formed

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by adding the suffix -aceae to the stem of a legitimate name of an included genus
(see also Art. 10). (For the treatment of final vowels of sterns in composition, see
Rec 73G).

Examples: Rosaceae (from Rosa), Salicaceae (from Salix), Plumbaginaceae (from Plumbago),

Caryophyllaceae, nom. cons. (from Caryophylus Mill. non L.), Winteraceae, nom. cons. (from
Wintera Murr., an illegitimate synonym of Drimys J. R. et G. Forst.).

Names intended as names of families, but published with their rank denoted by
one of the terms order (ordo) or natural order (ordo naturalis) instead of family,
are treated as having been published as names of families.

Note 1. A name of a family based on the stem of an illegitimate generic name
is illegitimate unless conserved. Contrary to Art. 32 (2) such a name is validly
published if it complies with the other requirements for valid publication.

Note 2. When a name of a family has been published with an improper termina-
tion, the ending is to be changed to accord with the rule, without change of the
author’s name. (See Art. 32, Note 1.)

Note 3. The following names, sanctioned by long usage, are treated as validly
published: Palmae (Arecaceae; type, Areca L.); Gramineae (Poaceae; type, Poa L.);
Cruciferae (Brassicaceae; type, Brassica L.); Leguminosae (Fabaceae; type, Faba
Mill. (= Vicia L. p.p.); Guttiferae (Clusiaceae; type, Clusia L.); Umbelliferae
(Apiaceae; type, Apium L.); Labiatae (Lamiaceae; type, Lamium L.); Compositae
(Asteraceae; type, Aster L.).

Botanists are authorized, however, to use as alternatives the appropriate names
ending in -aceae.

When the Papilionaceae are regarded as a family distinct from the remainder
of the Leguminosae, the name Papilionaceae is conserved against Leguminosae. The

alternative name is Fabaceae. This is an unique exception to Art. 51.

Article 19

The name of a subfamily is a plural adjective used as a substantive; it is formed
by adding the suffix -oideae to the stem of a legitimate name of an included genus.

A tribe is designated in a similar manner, with the ending -eae, and a subtribe
similarly with the ending -inae.

The name of any taxon of a rank below family and above genus which includes
the type genus of the correct name of the family to which it is assigned is to be based
on the name of that genus, but without the citation of an author’s name (see Art. 46).

This provision applies only to the names of those taxa which include the type of the
correct name of the family; the type of the correct name of each such taxon is the
same as that of the correct name of the family.

Note 1. Names of other taxa of a rank below family and above genus are subject
to the provisions of priority.

Examples: The subfamily including the type genus of the family Ericaceae (Erica L.) is
called subfamily Ericoideae, and the tribe including this genus is called tribe Ericeae. How-
ever, the correct name of the tribe including both Rhododendron L., the type genus of the
subfamily Rhododendroideae Endl., and Rhodora L. is Rhodoreae G. Don (the oldest legitimate
name), and not Rhododendreae.

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The subfamily of the family Asteraceae (nom. alt., Compositae) including Aster L., the
type genus of the family name, is called subfamily Asteroideae, and the tribe and subtribe
including Aster are called Astereae and Asterinae, respectively. However, the correct name of
the tribe including both Cichorium L., the type genus of the subfamily Cichorioideae Kita-
mura, and Lactuca L. is Lactuceae Cass., not Cichorieae, while that of the subtribe including
both Cichorium and Hyoseris L. is Hyoseridinae Less., not Cichoriinae.

The first valid publication of a name of a taxon at a rank below family and above
genus which does not include the type of the correct name of the family automatically
establishes the name of another taxon at the same rank which does include that type.
Such autonyms (automatically established names) are not to be taken into conside-
ration for purposes of priority. However, when no earlier name is available, they may
be adopted as new in another position.

The name of a subdivision of a family may not be based on the same stem of a
generic name as is the name of the family or of any subdivision of the same family
unless it has the same type as that name.

Note 2. When a name of a taxon assigned to one of the above categories has been
published with an improper termination, such as -eae for a subfamily or -oideae
for a tribe, the ending must be changed to accord with the rule, without change
of the author’s name. However, when the rank of the group is changed by a later
author, his name is then cited as author for the name with the appropriate ending,
in the usual way.

Example: The subfamily name Climacieae Grout (Moss Fl. N. Am. 3; 4. 1928) is to be
changed to Climacioideae with rank and author’s name unchanged. If it is held necessary
to change the rank of this taxon to a tribe, then the name Climacieae is to be used followed
by the name of the author making the change.

Recommendation 19A

If a legitimate name is not available for a taxon of a rank below family and above genus
which includes the type genus of the name of another higher or lower taxon (e.g., subfamily,
tribe, or subtribe), but not that of the family to which it is assigned, the new name of that
taxon should be based on the same generic name as the name of the higher or lower taxon.

Examples: Three tribes of the family Ericaceae, none of which includes the nomenclatural
type of the family (Erica L.), are Pyroleae D. Don, Monotropeae D. Don, and Vaccinieae D.
Don. The names of the later-described subfamilies Pyroloideae A. Gray, Monotropoideae
A. Gray, and Vaccinioideae Endl. are based on the same generic names.

Section 3. NAMES OF GENERA AND SUBDIVISIONS OF GENERA

Article 20

The name of a genus is a substantive in the singular number, or a word treated
as such. It may be taken from any source whatever, and may even be composed in
an absolutely arbitrary manner.

Examples: Rosa, Convolvulus, Hedysarum, Bartramia, Liquidambar, Gloriosa, Impatiens,
Rhododendron, Manihot, Ifloga (an anagram of Filago).

The name of a genus may not coincide with a technical term currently used in
morphology unless it was published before 1 Jan. 1912 and was accompanied, when

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originally published, by a specific name published in accordance with the binary
system of Linnaeus.

Examples: The generic name Radicula Hill (Brit. Herbal 264. 1756) coincides with the
technical term radicula (radicle) and, when originally published, was not accompanied by
a specific name in accordance with the Linnaean system. The name is correctly attributed
to Moench (Meth. 262. 1794), who first combined it with specific epithets, but at that time
he included in the genus the type-species of the generic name Rorippa Scop. (F1. Carn. 520.
1760). Radicula Moench is therefore rejected in favour of Rorippa.

Tuber Micheli ex Fr. (Syst. Myc. 2: 289. 1823) was accompanied by binary specific
names, e.g. Tuber cibarium, and is therefore admissible.

Names such as Radix, Caulis, Folium, Spina, etc., cannot now be validly published as
new generic names.

The name of a genus may not consist of two words, unless these words are joined
by a hyphen.

Examples: The generic name Uva ursi Mill. (Gard. Dict. Abr. ed. 4. 1754) as originally
published consisted of two separate words unconnected by a hyphen, and is therefore rejected;
the name is correctly attributed to Duhamel (Traité Arbr. Arbust. 2: 371. 1755) as Uva-ursi
(hyphened when published).

However, names such as Quisqualis (formed by combining two words into one when
originally published), Sebastiano-Schaueria, and Neves-Armondia (both hyphened when
originally published) are admissible.

Note. The names of intergeneric hybrids are formed according to the provisions
of Appendix I, Art. H. 7.

The following are not to be regarded as generic names:

(1) Words not intended as names.

Examples: Anonymos Walt. (Fl. Carol. 2, 4, 9, etc. 1788) is rejected as being a word
applied to 28 different genera by Walter to indicate that they were without names.

Schaenoides and Scirpoides, used by Rottböll (Descr. Pl. Rar. Progr. 14, 27. 1772) to
indicate unnamed genera resembling Schoenus and Scirpus which he stated (on page 7)
he intended to name later, are token words and not generic names. Kyllinga Rottböll and
Fuirena Rottböll (Descr. Ic. Nov. Pl. 12, 70. 1773) are the first legitimate names of these
genera.

(2) Unitary designations of species.

Examples: F. Ehrhart (Phytophylacium 1780, and Beitr. 4: 145-150. 1789) proposed
unitary names for various species known at that time under binary names, e.g. Phaeocephalum
for Schoenus fuscus, and Leptostachys for Carex leptostachys. These names, which resemble
generic names, should not be confused with them and are to be rejected, unless they have
been published as generic names by a subsequent author; for example, the name Baeothryon,
employed as a unitary name of a species by Ehrhart, was subsequently published as a
generic name by A. Dietrich (Sp. Pl. 2(2): 89. 1833).

N. J. de Necker in his Elementa Botanica, 1790, proposed unitary designations for his
“species naturales”. These names, which resemble generic names, are not to be treated as
such, unless they have been published as generic names by a subsequent author; for example
Anthopogon, employed by Necker for one of his “species naturales”, was published as a
generic name by Rafinesque: Anthopogon Raf. (Fl. Tell. 3: 25). 1837, non Nuttall 1818).

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Recommendation 20A

Botanists who are forming generic names should comply with the following suggestions:

(a) To use Latin terminations insofar as possible.

(b) To avoid names not readily adaptable to the Latin language.

(d) Not to make names by combining words from different languages.

(e) To indicate, if possible, by the formation or ending of the name the affinities or
analogies of the genus.

(f) To avoid adjectives used as nouns.

(g) Not to use a name similar to or derived from the epithet of one of the species of
the taxon.

(h) Not to dedicate genera to persons quite unconnected with botany or at least with
natural science.

(i) To give a feminine form to all personal generic names, whether they commemorate
a man or a woman (see Rec. 73B).

    (j)   Not to form generic names by combining parts of two existing generic names, e.g.
           Hordelymus from Hordeum and Elymus, because such names are likely to be confused
           with names of intergeneric hybrids (see Art. H. 7).

Article 21

The name of a subdivision of a genus is a combination of a generic name and
a subdivisional epithet connected by a term (subgenus, section, series, etc.) denoting
its rank.

The epithet is either of the same form as a generic name, or a plural adjective
agreeing in gender with the generic name and written with a capital initial letter.

The epithet of a subgenus or section is not to be formed from the name of the
genus to which it belongs by adding the ending -oides or -opsis, or the prefix Eu-.

Examples: Costus subg. Metacostus; Ricinocarpos sect. Anomodiscus; Sapium subsect.
Patentinervia; Euphorbia sect. Tithymalus subsect. Tenellae; but not Carex sect. Eucarex.

Note 1. The use within the same genus of the same epithet for subdivisions of
the genus, even if they are of different rank, based on different types is illegitimate
under Art. 64.

Note 2. The names of hybrids with the rank of a subdivision of a genus are
formed according to the provisions of Appendix I, Art. H. 7.

Recommendation 21A

When it is desired to indicate the name of a subdivision of the genus to which a
particular species belongs in connection with the generic name and specific epithet, its
epithet is placed in parentheses between the two; when necessary, its rank is also indicated.

Examples: Astragalus (Cycloglottis) contortuplicatus; Astragalus (Phaca) umbellatus; Lor-
anthus (sect. Ischnanthus) gabonensis.

Recommendation 21B

The epithet of a subgenus or section is preferably a substantive, that of a subsection
or lower subdivision of a genus preferably a plural adjective.

Botanists, when proposing new epithets for subdivisions of genera, should avoid those
in the form of a substantive when other co-ordinate subdivisions of the same genus have
them in the form of a plural adjective, and vice-versa.

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They should also avoid, when proposing an epithet for a subdivision of a genus, one
already used for a subdivision of a closely related genus, or one which is identical with
the name of such a genus.

If it is desired to indicate the resemblance of a subgenus or section (other than the type
subgenus or section) of one genus to another genus, the ending -oides or -opsis may be
added to the name of that other genus to form the epithet of the subgenus or section
concerned.

Article 22

The subgenus or section (but not subsection or lower subdivision) including the
type species of the correct name of the genus to which it is assigned bears that generic
name unaltered as its epithet, but without citation of an author’s name (see Art. 46).
The type of the correct name of each such subgenus or section is the same as that
of the generic name. This provision does not apply to sections which include the
type species of the names of other subgenera of the genus. The names of such sections
are subject to the provisions of priority; they may repeat the name of the subgenus
if no other epithet is available (see Rec. 22A).

The first valid publication of a name of a subgenus or section which does not
include the type of the correct name of the genus automatically establishes the name
of another subgenus or section respectively which does include that type and which
bears as its epithet the generic name unaltered. Such autonyms (automatically estab-
lished names) are not to be taken into consideration for purposes of priority. How-
ever, when no other epithet is available, the epithets of autonyms may be adopted
as new in another position or rank.

Examples: The subgenus of Malpighia L. which includes the lectotype of the generic name
(M. glabra L.) is called Malpighia subg. Malpighia, and not Malpighia subg. Homoiostylis
Niedenzu. Similarly, the section including the lectotype of the generic name is called Mal-
pighia sect. Malpighia, and not Malpighia sect. Apyrae DC.

However, the correct name of the section of the genus Phyllanthus which includes both
P. casticum Willem., the type of the subgenus Kirganelia (Juss.) Webster, and P. reticulatus
Poir., the type of the section Anisonema (Juss.) Griseb., is Phyllanthus sect. Anisonema (Juss.)
Griseb., the oldest legitimate name for that section, and not Phyllanthus sect. Kirganelia.

The final epithet in the name of a subdivision of a genus may not repeat unchanged
the correct name of the genus, except when the two names have the same type.

When the epithet of a subdivision of a genus is identical with or derived from
the epithet of one of its constituent species, this species is the type of the name of
the subdivision of the genus unless the original author of that name designated
another type.

Examples: The type of Euphorbia subg. Esula Persoon (Syn. Pl. 2: 14. 1806) is E. esula L.;
the designation of E. peplus L. as lectotype by Croizat (Rev. Sudamer. Bot. 6: 13. 1939) is
rejected. The type of Lobelia sect. Eutupa Wimmer (Ann. Nat. Mus. Wien 61: 365. 1948)
is L. tupa L.

Note. When the epithet of a subdivision of a genus is identical with or derived
from the epithet of a specific name that is a later homonym, it is the species
designated by that later homonym, whose correct name necessarily has a different
epithet, that is the nomenclatural type.

Recommendation 22A

A section including the type of the correct name of a subgenus, but not including the type
of the correct name of the genus, should, where there is no obstacle under the rules, be given
the same epithet and type as the subgenus.

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A subgenus not including the type of the correct name of the genus should, where there
is no obstacle under the rules, be given the same epithet and type as one of its subordinate
sections.

Example: Instead of using a new name at the subgeneric level, Brizicky raised Rhamnus L.
sect. Pseudofrangula Grubov to the rank of subgenus as Rhamnus subg. Pseudofrangula
(Grubov) Brizicky. The type species of both names is tbe same, R. alnifolia L’Hér.

Section 4. NAMES OF SPECIES

Article 23

The name of a species is a binary combination consisting of the name of the
genus followed by a single specific epithet. If an epithet consists of two or more
words, these are to be united or hyphened. An epithet not so joined when originally
published is not to be rejected but, when used, is to be united or hyphened.

The epithet of a species may be taken from any source whatever, and may even
be composed arbitrarily.

Examples: Cornus sanguinea, Dianthus monspessulanus, Papaver rhoeas, Uromyces fabae,
Fumaria gussonei, Geranium robertianum, Embelia sarasinorum, Atropa bella-donna, Im-
patiens noli-tangere, Adiantum capillus-veneris, Spondias mombin (an indeclinable epithet).

Symbols forming part of specific epithets proposed by Linnaeus must be tran-
scribed.

Examples: Scandix pecten ♀ L. is to be transcribed as Scandix pecten-veneris; Veronica
anagallis∇ L. is to be transcribed as Veronica anagallis-aquatica.

The specific epithet may not exactly repeat the generic name with or without the
addition of a transcribed symbol (tautonym).

Examples: Linaria linaria, Nasturtium nasturtium-aquaticum.

The specific epithet, when adjectival in form and not used as a substantive, agrees
grammatically with the generic name.

Examples: Helleborus niger, Brassica nigra, Verbascum nigrum; Rubus amnicola, the
specific epithet being an invariable Latin substantive; Peridermium balsameum Peck, but also
Gloeosporium balsameae J. J. Davis, both derived from the epithet of Abies balsamea, the
specific epithet of which is treated as a substantive in the second example.

The following are not to be regarded as specific epithets:

(1) Words not intended as names.

Examples: Viola “qualis” Krocker (Fl. Siles. 2: 512, 517. 1790); Atriplex “nova” Winterl
(Ind. Hort. Bot. Univ. Pest. fol. A. 8, recto et verso, 1788), the word “nova” being here used
in connection with four different species of Atriplex.

(2) Ordinal adjectives used for enumeration.

Examples: Boletus vicesimus sextus, Agaricus octogesimus nonus.

(3) Epithets published in works in which the Linnaean system of binary nomen-
clature for species is not consistently employed.

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Example: The name Abutilon album Hill (Brit. Herbal 49. 1756) is a descriptive phrase
reduced to two words, not a binary name in accordance with the Linnaean system, and is
to be rejected: Hill’s other species was Abutilon flore flavo.

(4) Formulae designating hybrids (see Art. H. 4).

Note. Linnaeus is regarded as having used binary nomenclature for species con-
sistently from 1753 onwards, although there are exceptions, e.g. Apocynum fol.
androsaemi L. (Sp. Pl. 213. 1753 ≡ Apocynum androsaemifolium L. Sp. Pl. ed. 2.
311. 1762).

Recommendation 23A

Names of men and women and also of countries and localities used as specific epithets
may be substantives in the genitive (clusii, saharae) or adjectives (clusianus, dahuricus) (see
also Art. 73).

It will be well, in the future, to avoid the use of the genitive and the adjectival form
of the same word to designate two different species of the same genus; for example,
Lysimachia hemsleyana Maxim. (1891) and L. hemsleyi Franch. (1895).

Recommendation 23B

In forming specific epithets, botanists should comply also with the following suggestions:

(a) To use Latin terminations insofar as possible.

(b) To avoid epithets which are very long and difficult to pronounce in Latin.

(d) To avoid those formed of two or more hyphened words.

(e) To avoid those which have the same meaning as the generic name (pleonasm).

(f) To avoid those which express a character common to all or nearly all the species of
a genus.

(g) To avoid in the same genus those which are very much alike, especially those which
differ only in their last letters or in the arrangement of two letters.

(h) To avoid those which have been used before in any closely allied genus.

    (i)   Not to adopt unpublished names found in correspondence, travellers’ notes, herbarium
            labels, or similar sources, attributing them to their authors, unless these authors have
            approved publication.

(j) To avoid using the names of little-known or very restricted localities, unless the
species is quite local.

Section 5. NAMES OF TAXA BELOW THE RANK OF SPECIES

(INFRASPECIFIC TAXA)

Article 24

The name of an infraspecific taxon is a combination of the name of a species

and an infraspecific epithet connected by a term denoting its rank. Infraspecific
epithets are formed as those of species and, when adjectival in form and not used
as substantives, they agree grammatically with the generic name.

Infraspecific epithets such as typicus, originalis, originarius, genuinus, verus, and
veridicus, purporting to indicate the taxon containing the nomenclatural type of the
next higher taxon, are inadmissible and cannot be validly published except where
they repeat the specific epithet because Art. 26 requires their use.

The use of a binary combination for an infraspecific taxon is not admissible.

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Examples: Andropogon ternatus subsp. macrothrix (not Andropogon macrothrix); Herniaria

hirsuta var. diandra (not Hernaria diandra); Trifolium stellatum forma nanum (not nana).

Names published in the form of e.g. Andropogon ternatus subsp. A. macrothrix are to be
altered to the proper form without change of author’s name.

Saxifraga aizoon subforma surculosa Engler & Irmscher can also be cited as Saxifraga
aizoon var. aizoon subvar. brevifolia forma multicaulis subforma surculosa Engler & Irmscher;
by this a full classification of the subforma within the species is given.

Infraspecific taxa within different species may bear the same epithets; those
within one species may bear the same epithets as other species (but see Rec. 24B).

Examples: Rosa jundzillii var. leioclada and Rosa glutinosa var. leioclada; Viola tricolor
var. hirta in spite of the previous existence of a different species named Viola hirta.

Note. The use within the same species of the same epithet for infraspecific taxa,
even if they are of different rank, based on different types is illegitimate under
Art. 64.

Example: Erysimum hieraciifolium subsp. strictum var. longisiliquum and E. hieraciifolium
subsp. pannonicum var. longisiliquum.

Recommendation 24A

Recommendations made for specific epithets (see Recs. 23A, B) apply equally to infra-
specific epithets.

Recommendation 24B

Botanists proposing new infraspecific epithets should avoid those previously used for
species in the same genus.

Article 25

For nomenclatural purposes, a species or any taxon below the rank of species
is regarded as the sum of its subordinate taxa, if any.

Article 26

The name of an infraspecific taxon which includes the type of the correct name
of the species has as its final epithet the same epithet, unaltered, as that of the correct
name of the species, but without citation of an author’s name (see Art. 46). The
type of the correct name of each such infraspecific taxon is the same as that of the
correct name of the species. If the epithet of the species is changed, the names of
those infraspecific taxa which include the type of the name of the species are changed
accordingly.

Examples: The combination Lobelia spicata var. originalis McVaugh, which includes the
type of the name Lobelia spicata Lam., is to be replaced by Lobelia spicata Lam. var. spicata.

Because under Lobelia siphilitica L. there is described var. ludoviciana A. DC., one must
write Lobelia siphilitica L. var. siphilitica if only that part of L. siphilitica L. which includes
the type is meant.

The first valid publication of a name of an infraspecific taxon which does not
include the type of the correct name of the species automatically establishes the name
of a second taxon of the same rank which does include that type and has the same

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epithet as the species. Such autonyms (automatically established names) are not to
be taken into consideration for purposes of priority. Where no other epithet is
available, the epithets of autonyms may be adopted as new in another position or
rank.

Examples: The publication in 1843 of the name Lycopodium inundatum var. bigelovii
Tuckerm. automatically established the name of another variety, Lycopodium inundatum L.
var. inundatum, the type of which is that of the name Lycopodium inundatum L.

If Campanula gieseckiana subsp. groenlandica (Berlin) Böcher and C. gieseckiana Vest ex
Roem. & Schult. subsp. gieseckiana are united as a subspecies of C. rotundifolia L., the
correct name is C. rotundifolia subsp. groenlandica (Berlin) Löve & Löve, since the sub-
specific epithet gieseckiana is not to be taken into consideration for purposes of priority.

In the classification adopted by Rollins & Shaw, Lesquerella lasiocarpa (Hook. ex A. Gray)
Wats. is composed of two subspecies, subsp. lasiocarpa (which includes the type of the name
of the species and is cited without an author) and subsp. berlandieri (A. Gray) Rollins &
Shaw. The latter subspecies is composed of two varieties. In this classification the correct
name of the variety which includes the type of subsp. berlandieri is not L. lasiocarpa var.
berlandieri (A. Gray) Payson (1922) nor the autonym L. lasiocarpa var. berlandieri (cited
without an author) but is instead L. lasiocarpa var. hispida (Wats.) Rollins & Shaw, based on
Synthlipsis berlandieri A. Gray var. hispida Wats. (1882), the oldest legitimate varietal name.

Recommendation 26A

A variety including the type of the correct name of a subspecies, but not including the
type of the correct name of the species, should, where there is no obstacle under the rules,
be given the same epithet and type as the subspecies. A subspecies not including the type
of the correct name of the species should, where there is no obstacle under the rules, be
given the same epithet and type as one of its subordinate varieties.

A taxon of lower rank than variety which includes the type of the correct name of a
subspecies or variety, but not the type of the correct name of the species, should, where
there is no obstacle under the rules, be given the same epithet and type as the subspecies or
variety. On the other hand, a subspecies or variety which does not include the type of the
correct name of the species shouid not be given the same epithet as that of one of its sub-
ordinate taxa below the rank of variety.

Examples: Fernald treated Stachys palustris subsp. pilosa (Nutt.) Epling (1934) as com-
posed of five varieties, for one of which (that including the type of subsp. pilosa) he made
the combination S. palustris var. pilosa (Nutt.) Fern. (1934), there being no legitimate varietal
epithet available.

There being no legitimate epithet available at the rank of subspecies, Bonaparte (1915)
made the combination Pteridium aquilinum subsp. caudatum (L.) Bonap., using the same
epithet that Sadebeck had used earlier (1897) in the combination P. aquilinum var. caudatum
(L.) Sadeb. (both names based on Pteris caudata L.). Each name is correct in its own rank,
and both can be used, as by Tryon (1940), who treated P. aquilinum var. caudatum as one
of four varieties under subspecies caudatum.

Article 27

The final epithet in the name of an infraspecific taxon may not repeat unchanged
the epithet of the correct name of the species to which the taxon is assigned except
when the two names have the same type.

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Section 6. NAMES OF PLANTS IN CULTIVATION

Article 28

Plants brought from the wild into cultivation retain the names that are applied to
the same taxa growing in nature.

Examples: Davallia canariensis and Spiraea hypericifolia var. obovata are taxa having the
same name in both the wild and in cultivation. Forms of Chrysanthemum parthenium brought
into cultivation are not to be renamed Matricaria eximia, Chiastophyllum (Cotyledon) oppositi-
folium brought into cultivation is not to be renamed Cotyledon simplicifolia.

Variants of infraspecific rank, which arise in cultivation through hybridization,
mutation, selection or other processes, and which are of sufficient interest to cul-
tivators to be distinguished by a name, receive cultivar epithets preferably in com-
mon language (i.e. fancy epithets) markedly different from the Latin epithets of
species and varieties.

Examples: Anemone × hybrida ‘Honorine Jaubert’, Fraxinus excelsior ‘Westhofs Glorie’:
Juglans regia ‘King’, Primula malacoides ‘Pink Sensation’ and Viburnum × bodnantense
‘Dawn’ are variants which have arisen in cultivation and are recognized as cultivars.

Variants found growing in the wild: which are brought into cultivation, may
also be given cultivar epithets.

Examples: Phlox nivalis ‘Gladwyne’ and P. nivalis ‘Azure’ are variants taken into cultiva-
tion from the wild for their horticultural interest.

Detailed regulations for the nomenclature of plants in cultivation, including graft-
chimaeras (sometimes called “graft hybrids”), appear in the International Code of
Nomenclature of Cultivated Plants.

For names of hybrid groups, both wild and cultivated, see Art. 40 and Appendix I.

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Chapter IV. EFFECTIVE AND VALID PUBLICATION

Section 1. CONDITIONS AND DATES OF EFFECTIVE PUBLICATION

Article 29

Publication is effected, under this Code, only by distribution of printed matter
(through sale, exchange, or gift) to the general public or at least to botanical institu-
tions with libraries accessible to botanists generally. It is not effected by communica-
tion of new names at a public meeting, by the placing of names in collections or
gardens open to the public, or by the issue of microfilm made from manuscripts,

type-scripts or other unpublished material. Offer for sale of printed matter that does
not exist does not constitute effective publication.

Publication by indelible autograph before 1 Jan. 1953 is effective.

Note. For the purpose of this Article, handwritten material, even though repro-
duced by some mechanical or graphic process (such as lithography, offset, or metallic
etching), is still considered as autographic.

Examples: Effective publication without printed matter: Salvia oxyodon Webb et Heldr.
was published in July 1850 in an autograph catalogue placed on sale (Webb et Heldreich,
Catalogus Plantarum Hispanicarum . . . ab A. Blanco lectarum, Paris, July 1850, folio).

Effective publication in reproduced handwritten material: H. Léveillé, Flore du Kouy
Tchéou (1914-15), a work lithographed from the handwritten manuscript.

Non-effective publication at a public meeting: Cusson announced his establishment of
the genus Physospermum in a memoir read at the Société des Sciences de Montpellier in
1770, and later in 1782 or 1783 at the Société de Médecine de Paris, but its effective
publication dates from 1787 in the Mémoires de la Société Royale de Médecine de Paris
5(1): 279.

Publication on or after 1 Jan. 1953 of a new name in tradesmen’s catalogues or
non-scientific newspapers, and on or after 1 Jan. 1973 in seed-exchange lists, does
not constitute effective publication.

Recommendation 29A

Authors are urged to avoid publishing new names or descriptions in ephemeral publica-
tions, in popular periodicals, in any publication unlikely to reach the general botanical public,
in those produced by such methods that their permanence is unlikely, or in abstracting
journals.

Article 30

The date of effective publication is the date on which the printed matter became
available as defined in Art. 29. In the absence of proof establishing some other date,
the one appearing in the printed matter must be accepted as correct.

Example: Individual parts of Willdenow’s Species Plantarum were published as follows:
1(1). 1797; 1(2), 1798; 2(1), 1799; 2(2), 1799 or January 1800; 3(1) (to page 850), 1800; 3(2)

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(to page 1470), 1802; 3(3) (to page 2409), 1803 (and later than Michaux’s Flora boreali-
americana); 4(1) (to page 630), 1805; 4(2), 1806; these dates, which are partly in disagree-
ment with those on the title-pages of the volumes, are the dates of publication (see Rhodora
44: 147-150. 1942).

When separates from periodicals or other works placed on sale are issued in
advance, the date on the separate is accepted as the date of effective publication
unless there is evidence that it is erroneous.

Example: Publication in separates issued in advance: the Selaginella species published
by Hieronymus in Hedwigia 51: 241-272 (1912) were effectively published on 15 Oct. 1911,
since the volume in which the paper appeared states (p. ii) that the separate appeared on
that date.

Recommendation 30A

The date on which the publisher or his agent delivers printed matter to one of the usual
carriers for distribution to the public should be accepted as its date of publication.

Article 31

The distribution on or after 1 Jan. 1953 of printed matter accompanying exsiccata
does not constitute effective publication.

Note. If the printed matter is also distributed independently of the exsiccata,
this constitutes effective publication.

Example: Works such as Schedae operis . . . plantae finlandiae exsiccatae, Helsingfors 1.
1906, 2. 1916, 3. 1933, 1944, or Lundell et Nannfeldt, Fungi exsiccati suecici etc., Uppsala
1-. . ., 1934-. . ., distributed independently of the exsiccata, whether published before or
after 1 Jan. 1953, are effectively published.

Section 2. CONDITIONS AND DATES OF VALID PUBLICATION OF NAMES

Article 32

In order to be validly published, a name of a taxon must (1) be effectively
published (see Art. 29); (2) have a form which complies with the provisions of
Arts. 16–27 (but see Art. 18, notes 1, 2, and 3) and Art. H. 7; (3) be accompanied
by a description or diagnosis * of the taxon or by a reference (direct or indirect)
to a previously and effectively published description or diagnosis of it (except as
provided in Art. H. 9); and (4) comply with the special provisions of Arts. 33–45.

Note 1. Names published with an incorrect Latin termination but otherwise in
accordance with this Code are regarded as validly published; they are to be changed
to accord with Arts. 17–19, 21, 23, and 24, without change of the author’s name.

Note 2. An indirect reference is a clear indication, by the citation of the author’s
name or in some other way, that a previously and effectively published description
or diagnosis applies to the taxon to which the new name is given.

Examples of names not validly published: Egeria Néraud (in Gaudichaud, in de Freycinet,
Voyage Monde Uranie et Physicienne, Bot. 25, 28. 1826), published without a description
or a diagnosis or a reference to a former one.

The name Loranthus macrosolen Steud. originally appeared without a description or

———————

* A diagnosis of a taxon is a statement of that which in the opinion of its author distinguishes
the taxon from others.

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diagnosis on the printed tickets issued about the year 1843 with Sect. II. no. 529, 1288,
of Schimper’s herbarium specimens of Abyssinian plants; it was not validly published,
however, until A. Richard (Tent. Fl. Abys. 1: 340. 1847) supplied a description.

Examples of indirect reference: Kratzmannia Opiz (in Berchtold et Opiz, Oekon.-techn.
Fl. Böhmens 1/2: 398. 1836) is published with a diagnosis, but it was not definitely accepted
by the author and is therefore not validly published. It is accepted definitely in Opiz,
Seznam Rostlin Květeny České 56 (1852), but without any description or diagnosis. The
citation of “Kratzmannia O.” includes an indirect reference to the previously published
diagnosis in 1836.

Opiz published the name of the genus Hemisphace (Benth.) Opiz in Seznam Rostlin
Květeny České 50 (1852) without a description or diagnosis, but as he wrote Hemisphace
Benth. he indirectly referred to the previously validly published description by Bentham,
Labiat. Gen. Sp. 193 (1833), of Salvia sect. Hemisphace.

The publication of the new combination Cymbopogon martinii by W. Watson in Atkinson,
Gaz. NW. Provo India 10: 392 (1882) is validated by the addition of the number “309”,
which, as explained at the top of the same page, is the running-number of the species
(Andropogon martini Roxb.) in Steudel, Syn. Pl. Glum. 1: 388 (1854). Although the reference
to the synonym Andropogon martini is indirect, it is perfectly unambiguous.

Note 3. In certain circumstances an illustration with analysis is accepted as
equivalent to a description (see Arts. 42 and 44).

Note 4. For names of plant taxa originally published as names of animals, see
Art. 45.

Recommendation 32A

Publication of a name should not be validated solely by a reference to a description or
diagnosis published before 1753.

Recommendation 32B

The description or diagnosis of any new taxon should mention the points in which the
taxon differs from its allies.

Recommendation 32B

Authors should avoid adoption of a name or an epithet which has been previously but
not validly published for a different taxon.

Recommendation 32D

In describing new taxa, authors should, when possible, supply figures with details of
structure as an aid to identification.

In the explanation of the figures, it is valuable to indicate the specimen(s) on which
they are based.

Authors should indicate clearly and precisely the scale of the figures which they publish.

Recommendation 32E

The description or diagnosis of parasitic plants should always be followed by an indication
of the hosts, especially those of parasitic fungi. The hosts should be designated by their
scientific names and not solely by names in modern languages, the applications of which
are often doubtful.

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Article 33

A combination is not validly published unless the author definitely indicates that
the epithet or epithets concerned are to be used in that particular combination.

Examples of combinations definitely indicated: In Linnaeus’ Species Plantarum the
placing of the epithet in the margin opposite the name of the genus clearly indicates the
combination intended. The same result is attained in Miller’s Gardeners Dictionary, ed. 8,
by the inclusion of the epithet in parentheses immediately after the name of the genus, in
Steudel’s Nomenclator Botanicus by the arrangement of the epithets in a list headed by the
name of the genus, and in general by any typographical device which indicates that an
epithet is associated with a particular generic or other name.

Examples of combinations not definitely indicated: Rafinesque’s statement under Blephilia
(Journ. Phys. Chim. Hist. Nat. 89: 98. 1819) that “Le type de ce genre est la Monarda
ciliata Linn.” does not constitute publication of the combination Blephilia ciliata, since he
did not indicate that that combination was to be used. Similarly, the combination Eulophus
peucedanoides is not to be ascribed to Bentham on the basis of the listing of Cnidium
peucedanoides H.B.K. under Eulophus (Gen. Pl. 1: 885. 1867).

A new combination or a new name for a previously recognized taxon published
on or after 1 Jan. 1953 is not validly published unless its basionym (name-bringing
or epithet-bringing synonym) or the replaced synonym (when a new name or epithet
is proposed) is clearly indicated and a full and direct reference given to its author
and original publication with page or plate reference and date.

Note 1. Mere reference to the Index Kewensis, the Index of Fungi, or any work
other than that in which the name was validly published does not constitute a full
and direct reference to the original publication of a name.

Note 2. Bibliographic errors of citation do not invalidate the publication of a
new combination.

Example: Fernald, in making the combination Echinochloa muricata (Rhodora 17: 106.
1915), cited Panicum muricatum Michx. (1803) as basionym, although the latter is illegitimate,
being a later homonym of Panicum muricatum Retz. (1786). Beauvois (Ess. Agrost. 51, 170,
178. 1812) had previously made the combination Setaria muricata with basionym Panicum
muricatum Michx. Under the provisions of Art. 72, Setaria muricata Beauv. is treated as a
new name, not a new combination. The correct name of the species in the genus Echinochloa
is E. muricata (Beauv.) Fernald, and the date of valid publication is that by Fernald in 1915,
although the publication by Beauvois was not cited by Fernald in making the new com-
bination.

A name given to a taxon whose rank is at the same time denoted by a misplaced
term (one contrary to Art. 5) is treated as not validly published, examples of such
misplacement being a form divided into varieties, a species containing genera, or
a genus containing families or tribes.

An exception is made for names of the infrageneric taxa termed tribes (tribus)
in Fries’ Systema Mycologicum, which are treated as validly published.

Examples: The names Delphinium tribus Involuta Huth (Bot. Jahrb. 20: 365. 1895), tribus
Brevipedunculata Huth (Bot. Jahrb. 20: 368), etc., are not validly published, since Huth
misapplied the term “tribus” to a category of lower rank than section.

Gandoger, in his Flora Europae (1883—1891), applied the term species (“espèce”) and
used binary nomenclature for two categories of taxa of consecutive rank, the higher rank being
equivalent to that of species in contemporary literature. He misapplied the term species to
the lower rank and the names of these taxa (“Gandoger’s microspecies”) are not validly
published.

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Article 34

A name is not validly published (1) when it is not accepted by the author in the
original publication; (2) when it is merely proposed in anticipation of the future
acceptance of the group concerned, or of a particular circumscription, position, or
rank of the group (so-called provisional name); (3) when it is merely mentioned
incidentally; (4) when it is merely cited as a synonym; (5) by the mere mention
of the subordinate taxa included in the taxon concerned.

Note 1. Provision no. 1 does not apply to names or epithets published with a
question mark or other indication of taxonomic doubt, yet published and accepted
by the author.

Note 2. By “incidental mention” of a new name or combination is meant mention
by an author who does not intend to introduce the new name or combination
concerned.

Examples: (1) The name of the monotypic genus Sebertia Pierre (msc.) was not validly
published by Baillon (Bull. Soc. Linn. Paris 2: 945. 1891) because he did not accept it.
Although he gave a description of the taxon, he referred its only species Sebertia acuminata
Pierre (msc.) to the genus Sersalisia R. Br. as Sersalisia ? acuminata; under the provision of
Note 1 this combination is validly published. The name Sebertia Pierre (msc.) was later validly
published by Engler (in Engler & Prantl, Nat. Pflanzenfam. Nachtr. 1: 280. 1897).

(1) (2) The generic name Conophyton Haw., suggested by Haworth (Rev. Pl. Succ. 82.
1821) for Mesembryanthemum sect. Minima Haw. (Rev. Pl. Succ. 81. 1821) in the words
“If this section proves to be a genus, the name of Conophyton would be apt”, was not
validly published, since Haworth did not adopt that generic name nor accept that genus.
The correct name for the genus is Conophytum N. E. Brown (Gard. Chron. III. 71: 198.
1922).

(3) The generic name Jollya was mentioned incidentally by Pierre (Notes Bot. Sapot. 7.
1890) in the discussion of the stamens of another genus and was therefore not validly
published in that publication.

(4) Acosmus Desv. (in Desf. Cat. Pl. Hort. Paris ed. 3. 233. 1829), cited as a synonym
of the generic name Aspicarpa L. C. Rich., was not validly published thereby.

Ornithogalum undulatum Hort. Bouch. ex Kunth (Enum. 4: 348. 1843), cited as a synonym
under Myogalum boucheanum Kunth, was not validly published thereby; when transferred
to Ornithogalum, this species is to be called O. boucheanum (Kunth) Aschers. (Oest. Bot.
Zeitschr. 16: 192. 1866).

Similarly Erythrina micropteryx Poepp. was not validly published by being cited as a
synonym of Micropteryx poeppigiana Walp. (Linnaea 23: 740. 1850); the species concerned,
when placed under Erythrina, is to be called E. poeppigiana (Walp.) O. F. Cook (U.S. Dep.
Agr. Bull. 25: 57. 1901).

(5) The family name Rhaptopetalaceae Pierre (Bull. Soc. Linn. Paris 2: 1296. May 1897),
which was accompanied merely by mention of constituent genera, Brazzeia, Scytopetalum,
and Rhaptopetalum, was not validly published, as Pierre gave no description or diagnosis; the
family bears the later name Scytopetalaceae Engler (in Engler & Prantl, Nat. Pflanzenfam.
Nachtr. zu II-IV. 1: 242. 1897), which was accompanied by a description.

The generic name Ibidium Salisb. (Trans. Hort. Soc. London 1: 291. 1812) was published
merely with the mention of four included species. As Salisbury supplied no generic description
or diagnosis, his publication of Ibidium is invalid.

When, on or after 1 Jan. 1953, two or more different names (so-called alternative
names) are proposed simultaneously for the same taxon by the same author, none of
them is validly published (but see Art. 59).

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Examples: The species of Brosimum described by Ducke (Arch. Jard. Bot. Rio de Janeiro
3: 23-29. 1922) were published with alternative names under Piratinera added in a footnote
(pp. 23-24). The publication of these names, being effected before 1 Jan. 1953, is valid.

Euphorbia jaroslavii Poljakov (Not. Syst. Herb. Inst. Bot. Acad. URSS 15: 155. tab. 1953)
was published with an alternative name, Tithymalus jaroslavii. Neither name was validly
published. However, one of the names, Euphorbia yaroslavii, (with a different transliteration
of the initial letter) was validly published by Poljakov (Not. Syst. Herb. Inst. Bot. Acad.
URSS 21: 484. 1961), who effectively published it with a new reference to the earlier
publication and simultaneously rejected the other name.

Recommendation 34A

Authors should avoid publishing or mentioning in their publications unpublished names
which they do not accept, especially if the persons responsible for these names have not
formally authorized their publication (see Rec. 23B, i).

Article 35

A new name published on or after 1 Jan. 1953 without a clear indication of the
rank of the taxon concerned is not validly published.

For such names published before 1 Jan. 1953 the choice made by the first author
who assigned a definite rank is to be followed.

Article 36

In order to be validly published, a name of a new taxon of plants, the bacteria,
algae, and all fossils excepted, published on or after 1 Jan. 1935 must be accom-
panied by a Latin description or diagnosis or by a reference to a previously and
effectively published Latin description or diagnosis of the taxon. (But see Art. H. 9.)

Example: The names Schiedea gregoriana Degener, Fl. Hawaiiensis, fam. 119. 1936 (Apr.
9) and S. kealiae Caum et Hosaka, Bernice P. Bishop Mus. Occas. Papers 11(23): 3. 1936
(Apr. 10) were proposed for the same plant; the type of the former is a part of the original
material of the latter. Since the name S. gregoriana is not accompanied by a Latin description
or diagnosis, the later S. kealiae is the legitimate name.

In order to be validly published, a name of a new taxon of recent algae published
on or after 1 Jan. 1958 must be accompanied by a Latin description or diagnosis
or by a reference to a previously and effectively published Latin description or
diagnosis.

Recommendation 36A

Authors publishing names of new taxa of recent plants should give or cite a full description
in Latin in addition to the diagnosis.

Article 37

Publication on or after 1 Jan. 1958 of the name of a new taxon of the rank of
family or below is valid only when the nomenclatural type is indicated (see Arts.
7–10) except as permitted by Art. H. 9 for names of certain hybrids.

Recommendation 37A

The indication of the nomenclatural type should immediately follow the Latin description
or diagnosis and should be given by the insertion of the Latin word “typus” (or “holotypus”,
etc.) immediately before or after the particulars of the type so designated.

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Recommendation 37B

When the nomenclatural type of a new taxon is a specimen, the place where it is
permanently conserved should be indicated.

Article 38

In order to be validly published, a name of a new taxon of fossil plants of
specific or lower rank published on or after 1 Jan. 1912 must be accompanied by
an illustration or figure showing the essential characters, in addition to the descrip-
tion or diagnosis, or by a reference to a previously and effectively published
illustration or figure.

Article 39

In order to be validly published, a name of a new taxon of recent algae of
specific or lower rank published on or after 1 Jan. 1958 must be accompanied by
an illustration or figure showing the distinctive morphological features, in addition
to the Latin description or diagnosis, or by a reference to a previously and effectively
published illustration or figure.

Article 40

In order to be validly published, names of hybrids of specific or lower rank with
Latin epithets must comply with the same rules as those pertaining to names of non-
hybrid taxa of the same rank.

Examples: The name Nepeta × faassenii Bergmans (Vaste Pl. ed. 2. 544. 1939) with a
description in Dutch, and in Gentes Herb. 8: 64 (1949) with a description in English, is not
validly published, not being accompanied by or associated with a Latin description or
diagnosis. The name Nepeta × faassenii Bergmans ex Stearn (Journ. Roy. Hort. Soc. Lond.
75: 405. 1950) is validly published, being accompanied by a Latin description with designa-
tion of type.

The name Rheum × cultorum Thorsrud & Reisaeter (Norske Plantenavr. 95. 1948), being
here a nomen nudum, is not validly published.

The name Fumaria × salmonii Druce (List Brit. Pl. 4. 1908), is not validly published,
because only its presumed parentage F. densiflora × F. officinalis is stated here.

Note. For names of hybrids of the rank of genus or subdivision of a genus, see
Appendix I, Art. H. 9.

For purposes of priority, names and epithets in Latin form given to hybrids are
subject to the same rules as are those of non-hybrid taxa of equivalent rank.

Examples: The name × Solidaster Wehrhahn (in Bonstedt, Pareys Blumengärtn. 2: 525.
1932) antedates the name × Asterago Everett (Gard. Chron. III. 101. 6. 1937) for the hybrid
Aster × Solidago.

The name × Gaulnettya W. J. Marchant (Choice Trees, Shrubs 83. 1937) antedates the
name × Gaulthettia Camp (Bull. Torrey Bot. Club 66: 26. 1939) for the hybrid Gaultheria ×
Pernettya.

Anemone × hybrida Paxton (Mag. Bot. 15: 239. 1848) antedates A. × elegans Decaisne
(Revue Hort. IV. 1: 41. 1852), pro sp., as the binomial for the hybrids derived from A.
hupehensis × A. vitifolia.

In 1927, Aimée Camus (Bull. Mus. Nat. Hist. Nat. 33: 538. 1927) published the name
Agroelymus as the “generic” name of an intergeneric hybrid, without a Latin diagnosis or

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description, mentioning only the names of the parents involved (Agropyron and Elymus).
Since this name was not validly published under the Code then in force (Stockholm 1950),
Jacques Rousseau, in 1952 (Mém. Jard. Bot. Montréal 29: 10-11), published a Latin
diagnosis. However, the date of valid publication of the name Agroelymus under this Code
is 1927, not 1952, and the name also antedates × Elymopyrum Cugnac (Bull. Soc. Hist. Nat.
Ardennes 33: 14. 1938) which is accompanied by a statement of parentage and a description
in French but not Latin.

Article 41

In order to be validly published, a name of a genus must be accompanied (1) by
a description or diagnosis of the genus, or (2) by a reference (direct or indirect)
to a previously and effectively published description or diagnosis of the genus in
that rank or as a subdivision of a genus.

An exception is made for the generic names first published by Linnaeus in
Species Plantarum ed. 1 (1753) and ed. 2 (1762—63), which are treated as having
been validly published on those dates (see Art. 13, Note 3).

Note. In certain circumstances, an illustration with analysis is accepted as
equivalent to a generic description (see Art. 42).

Examples of validly published generic names: Carphalea Juss. (Gen. 198. 1789), accom-
panied by a generic description; Thuspeinanta Th. Dur. (Ind. Gen. Phan. x. 1888), accom-
panied by a reference to the previously described genus Tapeinanthus Boiss. (non Herb.);
Aspalathoides (DC.) K. Koch (Hort. Dendrol. 242. 1853), based on a previously described
section, Anthyllis sect. Aspalathoides DC.

Article 42

The publication of the name of a monotypic new genus based on a new species
is validated either by (1) the provision of a combined generic and specific descrip-
tion (descriptio generico-specifica) or diagnosis, or (2), for generic names published
before 1 Jan. 1908, by the provision of an illustration with analysis showing essential
characters (see Art. 32, Note 3).

Examples: Piptolepis phillyreoides Benth. (Pl. Hartw. 29. 1840) is a new species assigned
to the monotypic new genus Piptolepis published with a combined generic and specific
description. – The generic name Philgamia Baill. (in Grandidier, Hist. Madag. Pl. Atlas 3:
pl. 265. 1894) was validly published, as it appeared on a plate with analysis of P. hibbertioides
Baill. published before 1 Jan. 1908.

A description or diagnosis of a new species assigned to a monotypic new genus
is treated also as a generic description or diagnosis if the genus is not separately
defined. However, the name of a monotypic genus of fossil plants published on or
after 1 Jan. 1953 must be accompanied by a description or diagnosis of the genus.

A description or diagnosis of a monotypic new genus based on a new species is
treated also as a specific description or diagnosis if the generic name and specific
epithet are published together and the species is not separately defined.

Example: Strophioblachia fimbriicalyx Boerl. (Handl. Fl. Ned. Ind. 3(1): 236. 1900) is a
new species without separate definition, assigned to the monotypic new genus Strophioblachia
which is treated as published with a combined generic and specific description.

Note. Single figures of microscopic plants showing the details necessary for
identification are considered as illustrations with analysis showing essential
characters.

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Article 43

A name of a taxon below the rank of genus is not validly published unless the
name of the genus or species to which it is assigned is validly published at the same
time or was validly published previously.

Examples: Suaeda baccata, S. vera, and names for four other species of Suaeda were
published with diagnosis and descriptions by Forskål (Fl. Aegypt.-Arab. 69-71. 1775) but he
provided no diagnosis or description for the genus: these specific names were therefore, like
the generic name, not validly published by him.

In 1880, Müller Argoviensis (Flora 63: 286) published the new genus Phlyctidia with
the species P. hampeana n. sp., P. boliviensis (= Phlyctis boliviensis Nyl.), P. sorediiformis
(= Phlyctis sorediiformis Krempelh.), P. brasiliensis (= Phlyctis brasiliensis Nyl.), and
P. andensis (= Phlyctis andensis Nyl.). These specific names are, however, not validly
published in this place, because the generic name Phlyctidia was not validly published;
Müller gave no generic description or diagnosis but only a description and a diagnosis of
the new species P. hampeana. This description and diagnosis cannot validate the generic
name as a descriptio generico-specifica under Art. 42, since the new genus was not mono-
typic. The first valid publication of the name Phlyctidia was made by Müller in 1895
(Hedwigia 34: 141), where a short generic diagnosis was given. The only species mentioned
here were P. ludoviciensis n. sp. and P. boliviensis (Nyl.). The latter combination was validly
published in 1895 by the reference to the basionym.

Note. This Article applies also to specific and other epithets published under
words not to be regarded as generic names (see Art. 20).

Examples: The binary combination Anonymos aquatica Walt. (Fl. Carol. 230. 1788) is
not validly published. The correct name for the species concerned is Planera aquatica J. F.
Gmel. (1791), and the date of the epithet aquatica for purposes of priority is 1791. The
species must not be cited as Planera aquatica (Walt.) J. F. Gmel. If, however, it is desired
to indicate that the epithet originated with Walter, the name may be cited as Planera
aquatica Walt. ex J. F. Gmel.

The binary combination Scirpoides paradoxus Rottböll (Descr. Pl. Rar. Progr. 27. 1772) is
not validly published since Scirpoides is a word not intended as a generic name. The first
validly published name for this species is Fuirena umbellata Rottböll (Descr. Ic. Pl. 70. 1773).

Article 44

The name of a species or of an infraspecific taxon published before 1 Jan. 1908
is validly published if it is accompanied only by an illustration with analysis showing
essential characters (see Art. 32, Note 3).

Note. Single figures of microscopic plants showing the details necessary for
identification are considered as illustrations with analysis showing essential
characters.

Examples: Panax nossibiensis Drake (in Grandidier, Hist. Madag. Pl. Atlas 3: pl. 406.
1896), published on a plate with analyses. – Eunotia gibbosa Grunow (in Van Heurck, Syn.
Diat. Belg. pl. 35, fig. 13. 1881), a name of a diatom published with a single figure of
the valve.

Article 45

The date of a name or of an epithet is that of its valid publication. When the
various conditions for valid publication are not simultaneously fulfilled, the date
is that on which the last is fulfilled. A name published on or after 1 Jan. 1973 for

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which the various conditions for valid publication are not simultaneously fulfilled is
not validly published unless a full and direct reference is given to the place or places
where these requirements were previously fulfilled.

Example: Specimens of Mentha foliicoma Opiz were distributed by Opiz in 1832, but
the name dates from 1882, when it was validly published by Déséglise (Bull. Soc. Étud.
Sci. Angers 1881-82: 210. 1882).

Note. A correction of the original spelling of a name or epithet (see Art. 73)
does not affect its date of valid publication.

Example: The correction of the orthographic error in Gluta benghas L. (Mant. 293. 1771)
to Gluta renghas L. does not affect the date of publication of the epithet renghas (1771) even
though the correction dates only from 1883 (Engler in DC. Monogr. Phan. 4: 225).

For purposes of priority only legitimate names and epithets are taken into con-
sideration (see Arts. 11, 63–67). However, validly published earlier homonyms,
whether legitimate or not, shall cause rejection of their later homonyms (unless the
latter are conserved).

If a taxon is transferred from the animal to the plant kingdom, its name or
names available * under the International Code of Zoological Nomenclature and
validly published in the form provided in the botanical Code (except that for algae
validity under the zoological rules only is required) shall be automatically accepted
as having been validly published under this Code at the time of its valid publication
as the name of an animal (see, however, Art. 65).

Example: Amphiprora Ehrenberg (Abh. Preuss. Akad. Wiss. 1841: 401. 1843) was pub-
lished as the name of a genus of animals which was transferred to the plant kingdom in
1844 by Kuetzing; it has priority in botanical nomenclature from 1843, not 1844.

Recommendation 45A

Authors publishing a name of a new taxon in works written in a modem language (floras,
catalogues, etc.) should simultaneously comply with the requirements of valid publication.

Recommendation 45B

Authors should indicate precisely the dates of publication of their works. In a work
appearing in parts the last-published sheet of the volume should indicate the precise dates
on which the different fascicles or parts of the volume were published as well as the number
of pages and plates in each.

Recommendation 45C

On separately printed and issued copies of works published in a periodical, the date
(year, month, and day), the name of the periodical, the number of its volume or parts, and
the original pagination should be indicated.

———————

* The word “available” in the International Code of Zoological Nomenclature is equivalent
to “legitimate” in the International Code of Botanical Nomenclature.

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Section 3. CITATION OF AUTHORS’ NAMES AND OF LITERATURE

FOR PURPOSES OF PRECISION

Article 46

For the indication of the name of a taxon to be accurate and complete, and in
order that the date may be readily verified, it is necessary to cite the name of the
author(s) who first validly published the name concerned unless the provisions of
Arts. 19, 22, or 26 apply.

Examples: Rosaceae Juss., Rosa L., Rosa gallica L., Rosa gallica var. eriostyla R. Keller,
Rosa gallica L. var. gallica.

Recommendation 46A

Authors’ names put after names of plants may be abbreviated, unless they are very short.
For this purpose, particles are suppressed unless they are an inseparable part of the name,
and the first letters are given without any omission (Lam. for J.B.P.A. Monet Chevalier de
Lamarck, but De Wild. for É. De Wildeman).

If a name of one syllable is long enough to make it worth while to abridge it, the first
consonants only are given (Fr. for Elias Magnus Fries); if the name has two or more
syllables, the first syllable and the first letter of the following one are taken, or the two
first when both are consonants (Juss. for Jussieu, Rich. for Richard).

When it is necessary to give more of a name to avoid confusion between names beginning
with the same syllable, the same system is to be followed. For instance, two syllables are
given together with the one or two first consonants of the third; or one of the last charac-
teristic consonants of the name is added (Bertol. for Bertoloni, to distinguish it from Bertero;
Michx. for Michaux, to distinguish it from Micheli).

Given names or accessory designations serving to distinguish two botanists of the same
name are abridged in the same way (Adr. Juss. for Adrien de Jussieu, Gaertn. f. for Gaertner
filius, R. Br. for Robert Brown, A. Br. for Alexander Braun, J. F. Gmelin for Johann Friedrich
Gmelin, J. G. Gmelin for Johann Georg Gmelin, C. C. Gmelin for Carl Christian Gmelin,
S. G. Gmelin for Samuel Gottlieb Gmelin, Müll. Arg. for Jean Müller of Aargau).

When it is a well-established custom to abridge a name in another manner, it is best
to conform to it (L. for Linnaeus, DC. for de Candolle, St.-Hil. for Saint Hilaire, H.B.K.
for Humboldt, Bonpland et Kunth, F. v. Muell. for Ferdinand von Mueller).

Recommendation 46B

When a name has been published jointly by two authors, the names of both should be
cited, linked by means of the word et or by an ampersand (&).

When a name has been published jointly by more than two authors, the citation should
be restricted to that of the first one followed by et al.

Examples: Didymopanax gleasonii Britton et Wilson (or Britton & Wilson); Streptomyces
albo-niger Hesseltine, J. N. Porter, Deduck, Hauck, Bohonos, & J. H. Williams (Mycologia
46: 19. 1954) should be cited as S. albo-niger Hesseltine et al.

Recommendation 46C

When an author who first validly publishes a name ascribes it to another person, the
correct author citation is the name of the actual publishing author, but the name of the other
person, followed by the connecting word ex, may be inserted before the name of the pub-
lishing author, if desired. The same holds for names of garden origin ascribed to “hort.”
(hortulanorum).

Examples: Gossypium tomentosum Seem. or G. tomentosum Nutt. ex Seem. – Lithocarpus

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polystachya (A. DC.) Rehder or L. polystachya (Wall. ex A. DC.) Rehder – Orchis rotundi-
folia Pursh or O. rotundifolia Banks ex Pursh – Carex stipata Willd. or C. stipata Muhl. ex
Willd. – Gesneria donklarii Hook. or G. donklarii hort. ex Hook.

Recommendation 46D

When a name with a description or diagnosis (or reference to a description or diagnosis)
supplied by one author is published in a work by another author, the word in should be
used to connect the names of the two authors. In such cases the name of the author who
supplied the description or diagnosis is the most important and should be retained when it
is desirable to abbreviate such a citation.

Examples: Viburnum ternatum Rehder in Sargent, Trees and Shrubs 2: 37. 1907, or
Viburnum ternatum Rehder. – Teucrium charidemii Sandwith in Lacaita, Cavanillesia 3:
38. 1930, or Teucrium charidemii Sandwith.

Recommendation 46E

When an author who first validly publishes a name ascribes it to an author who published
the name before the starting point of the group concerned (see Art. 13), the author citation
may include, when such indication is considered useful or desirable, the name of the pre-
starting-point author followed by ex as in Rec. 46C.

Examples: Lupinus L. or Lupinus Tourn. ex L. – Boletus piperatus Fr. or B. piperatus
Bulliard ex Fr.

Recommendation 46F

Authors of new names of taxa should not use the expression nobis (nob.) or a similar
reference to themselves as an author citation but should cite their own names in each instance.

Article 47

An alteration of the diagnostic characters or of the circumscription of a taxon
without the exclusion of the type does not warrant the citation of the name of an
author other than the one who first published its name.

Examples: see under Art. 51.

Recommendation 47A

When the alteration mentioned in Art. 47 has been considerable, the nature of the change
may be indicated by adding such words, abbreviated where suitable, as emendavit (emend.)
(followed by the name of the author responsible for the change), mutatis characteribus (mut.
char.), pro parte (p.p.), excluso genere or exclusis generibus (excl. gen.), exclusa specie or
exclusis speciebus (excl. sp.), exclusa varietate or exclusis varietatibus (excl. var.), sensu amplo
(s. ampl.), sensu stricto (s. str.), etc.

Examples: Phyllanthus L. emend. Müll. Arg.; Globularia cordifolia L. excl. var. (emend.
Lam.).

Article 48

When an author circumscribes a taxon in such a way as to exclude the original
type of the name he uses for it, he is considered to have published a later homonym
that must be ascribed solely to him.

Example: Lemanea as treated by Sirodot (1872) explicitly excluded the type of Lemanea
Bory (1808) and hence is to be cited as Lemanea Sirodot and not Lemanea Bory emend.
Sirodot.

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Retention of a name in a sense that excludes the type can be effected only by
conservation. When a name is conserved with a type different from that of the
original author, the author of the name as conserved, with the new type, must
be cited.

Example: Bulbostylis Kunth, nom. cons. (non Bulbostylis Steven 1817). This is not to be
cited as Bulbostylis Steven emend. Kunth, since the type listed was not included in Bulbo-
stylis by Steven in 1817.

Article 49

When a genus or a taxon of lower rank is altered in rank but retains its name
or epithet, the author who first published this as a legitimate name or epithet (the
author of the basionym) must be cited in parentheses, followed by the name of
the author who effected the alteration (the author of the combination). The same
holds when a taxon of lower rank than genus is transferred to another taxon, with
or without alteration of rank.

Examples: Medicago polymorpha var. orbicularis L. when raised to the rank of species
becomes Medicago orbicularis (L.) Bartal. – Anthyllis sect. Aspalathoides DC. raised to generic
rank, retaining the name Aspalathoides, is cited as Aspalathoides (DC.) K. Koch.

Sorbus sect. Aria Pers. on transference to Pyrus is cited as Pyrus sect. Aria (Pers.) DC. –
Cheiranthus tristis L. transferred to the genus Matthiola becomes Matthiola tristis (L.) R. Br.

The species of Corydalis based on Fumaria bulbosa γ solida L. (1753) is cited as Corydalis
solida (L.) Sw. (1819) and not as Corydalis solida (Mill.) Sw. The latter citation refers to
Fumaria solida (L.) Mill. from 1771, also based on Fumaria bulbosa γ solida L.; the former,
correct citation refers to the first author of the legitimate epithet.

However, within the same species, Pulsatilla montana var. serbica Zimmermann (Feddes
Repert. 61: 95. 1958), originally placed under subsp. australis (Heuffel) Zamels, retains the
same author citation when placed under subsp. dacica Rummelspacher (see Art. 24) and is
not cited as var. serbica (Zimmermann) Rummelspacher (Feddes Repert. 71: 29. 1965).

Article 50

When the status of a taxon bearing a binary name is altered from species to
interspecific hybrid or vice versa, the name of the original author must be cited,
followed by an indication in parentheses of the original status. A similar indication
of original status must be given when an infraspecific taxon is altered in status to
nothomorph or vice versa (see Art. H. 10). If it is desirable or necessary to abbreviate
such a citation, the indication of the original status may be omitted.

Examples: Stachys ambigua J. E. Smith (Engl. Bot. 30: pl. 2089. 1810) was published as
a species. If regarded as a hybrid, it is cited as Stachys × ambigua J. E. Smith (pro sp.).

The binary name Salix × glaucops Anderss. (in DC. Prodr. 16(2): 281. 1868) was published
as the name of a hybrid. Later, Rydberg (Bull. N.Y. Bot. Gard. 1: 270. 1899) altered the
status of the taxon to that of a species. If this view is accepted, the name is cited as Salix
glaucops Anderss. (pro hybr.).

× Carya laneyi var. chateaugayensis Sarg. (Trees and Shrubs 2: 197. 1913) was published
as a variety; if regarded as a nothomorph, the name is cited as Carya × laneyi nm. chateau-
gayensis Sarg. (pro var.).

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Section 4. GENERAL RECOMMENDATIONS ON CITATION

Recommendation 50A

In the citation of a name published as a synonym, the words “as synonym” or pro syn.
should be added.

When an author has published as a synonym a manuscript name of another author, the
word ex should be used in citations to connect the names of the two authors (see Rec. 46C).

Example: Myrtus serratus, a manuscript name of Koenig published by Steudel as a
synonym of Eugenia laurina Willd., should be cited thus: Myrtus serratus Koenig ex Steudel,
Nomencl. 321 (1821) pro syn.

Recommendation 50B

In the citation of a nomen nudum, its status should be indicated by adding nomen nudum
(nom. nud.).

Recommendation 50C

When a name that is illegitimate because of an earlier homonym is cited in synonymy,
the citation should be followed by the name of the author of the earlier homonym preceded
by the word non, preferably with the date of publication added. In some instances it will
be advisable to cite also any later homonym, preceded by the word nec.

Examples: Ulmus racemosa Thomas, Am. Journ. Sci. 19: 170 (1831) non Borkh. 1800. –
Lindera Thunb. Nov. Gen. Pl. 64 (1783) non Adans. 1763. – Bartlingia Brongn. Ann. Sci.
Nat. 10: 373. (1827) non Reichb. 1824, nec F. v. Muell. 1877.

Recommendation 50D

Misidentifications should not be included in the synonymy but added after it. A mis-
applied name should be indicated by the words auct. non followed by the name of the
original author and the bibliographical reference of the misidentification.

Example: Ficus stortophylla Warb. in Warb. et De Wild. Ann. Mus. Congo, Bot. VI. 1:
32 (1904). F. irumuensis De Wild. Pl. Bequaert. 1: 341 (1922). F. exasperata auct. non Vahl:
De Wild. et Th. Dur. Ann. Mus. Congo, Bot. II. 1: 54. 1899; De Wild. Pl. Laur. 26 (1903);
Th. et H. Dur. Syll. Fl. Congol. 505 (1909).

Recommendation 50E

If a generic name is accepted as a nomen conservandum (see Art. 14 and App. III), the
abbreviation nom. cons. should be added to the citation.

Examples: Protea L. Mant. 187 (1771), nom. cons., non L. 1753. – Combretum Loefl.
1758 nom. cons. (syn. prius Grislea L. 1753). – Schouwia DC. (1821, Mai sero), nom. cons.
(homonymum prius Schouwia Schrad. 1821, Mai).

Recommendation 50F

A name cited in synonymy should be spelled exactly as published by its author. If any
explanatory words are required, these should be inserted in brackets. If a name is adopted
with alterations from the form as originally published, it is desirable that in full citations
the exact original form should be added, preferably between quotation marks.

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Examples: Pyrus calleryana Decne. (Pirus mairei Léveillé, Repert. Sp. Nov. 12: 189. 1913)
or (P. mairei Léveillé, Repert. Sp. Nov. 12: 189. 1913, ‘Pirus’), but not as Pyrus mairei.

Zanthoxylum cribrosum Spreng. Syst. 1: 946. 1825, ‘Xanthoxylon’ (Xanthoxylum caribaeum
var. floridanum (Nutt.) A. Gray, Proc. Am. Acad. 23: 225. 1888), but not as Z. caribaeum
var. floridanum (Nutt.) A. Gray.

Quercus bicolor Willd. (Q. prinus discolor Michx. f. Hist. Arb. For. 2: 46. 1811), but not
as Q. prinus var. discolor Michx. f.

Spiraea latifolia (Ait.) Borkh. (Spiraea salicifolia γ latifolia Ait. Hort. Kew. 2: 198. 1789),
but not as S. salicifolia latifolia Ait. or S. salicifolia var. latifolia Ait.

Juniperus communis var. saxatilis Pallas (J. communis [var.] 3 nana Loudon, Arb. Brit. 4:
2489. 1838). In this case ‘var.’ may be added in brackets, since Loudon classes this com-
bination under ‘varieties’.

Ribes tricuspis Nakai, Bot. Mag. Tokyo 30: 142. 1916, ‘tricuspe’.

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Chapter V. RETENTION, CHOICE, AND REJECTION OF NAMES

AND EPITHETS

Section 1. RETENTION OF NAMES OR EPITHETS OF TAXA

WHICH ARE REMODELLED OR DIVIDED

Article 51

An alteration of the diagnostic characters or of the circumscription of a taxon
does not warrant a change in its name, except as may be required (1) by trans-
ference of the taxon (Arts. 54—56), or (2) by its union with another taxon of the
same rank (Arts. 57, 58, Rec. 57A), or (3) by a change of its rank (Art. 60).

A unique exception is made for the family name Papilionaceae (see Art. 18,
Note 3).

Examples: The genus Myosotis as revised by R. Brown differs from the original genus of
Linnaeus, but the generic name has not been changed, nor is a change allowable, since the
type of Myosotis L. remains in the genus; it is cited as Myosotis L. or as Myosotis L. emend.
R. Br. (see Art. 47, Rec. 47A).

Various authors have united with Centaurea jacea L. one or two species which Linnaeus
had kept distinct; the taxon so constituted is called Centaurea jacea L. sensu amplo or
Centaurea jacea L. emend. Cosson et Germain, emend. Visiani, or emend. Godr., etc.; the
creation of a new name such as Centaurea vulgaris Godr. is superfluous and illegitimate.

Article 52

When a genus is divided into two or more genera, the generic name must be
retained for one of them or, if it has not been retained, must be reinstated for one
of them. When a particular species was originally designated as the type, the generic
name must be retained for the genus including that species. When no type has been
designated, a type must be chosen (see Guide for the determination of types, p. 75).

Examples: The genus Dicera J. R. et G. Forster (Char. Gen. Pl. 79. 1776) was divided
by Rafinesque (Sylva Tell. 60. 1838) into the two genera Misipus and Skidanthera; this
procedure is contrary to the rules: the name Dicera must be kept for one of the genera, and
it is now retained for that part of Dicera based on the lectotype, D. dentata.

The genus Aesculus L. contains the sections Aesculus, Pavia (Poir.) Pax, Macrothyrsus
(Spach) Pax, and Calothyrsus (Spach) Pax, the last three of which were regarded as distinct
genera by the authors cited in parentheses; in the event of these four sections being treated
as genera, the name Aesculus must be kept for the first of them, which includes the species
Aesculus hippocastanum L., as this species is the type of the genus founded by Linnaeus
(Sp. Pl. 344. 1753; Gen. Pl. ed. 5. 161. 1754); Tournefort’s name Hippocastanum is not to
be used for a genus including Aesculus hippocastanum L. as was done by P. Miller (Gard.
Dict. Abr. ed. 4. 1754).

Article 53

When a species is divided into two or more species, the specific epithet must be
retained for one of them or, if it has not been retained, must be reinstated for one
of them. When a particular specimen, description, or figure was originally designated

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as the type, the specific epithet must be retained for the species including that
element. When no type has been designated, a type must be chosen (see Guide for
the determination of types, p. 75).

Examples: Lychnis dioica L. (Sp. Pl. 437. 1753) was divided by Miller (Gard. Dict. ed. 8.
nos. 3, 4. 1768) into two species, L. dioica L. emend. Mill. and L. alba Mill.

G. F. Hoffmann (Deutschl. Fl. 3: 166. 1800) divided Juncus articulatus L. (1753) into
two species, J. lampocarpus Ehrh. ex Hoffm. and J. acutiflorus Ehrh. ex Hoffm. The name
J. articulatus L. ought, however, to have been retained for one of the segregate species, and
it has been reinstated in the sense of J. lampocarpus Ehrh. ex Hoffm. (see Briq., Prodr. Fl.
Corse 1: 264. 1910).

Genista horrida (Vahl) DC. (in Lam. et DC., Fl. Franç. ed. 3. 4: 500. 1805) was divided
by Spach (Ann. Sci. Nat. Bot. III. 2: 252. 1844) into three species, G. horrida (Vahl) DC.,
G. boissieri Spach, and G. webbii Spach; the name G. horrida was rightly kept for the
species including the plant from Jaca in Aragon originally described by Vahl (Symb. 1: 51.
1790) as Spartium horridum.

Two species (Primula cashmiriana Munro, P. erosa Wall.) have been separated from P.
denticulata J. E. Smith (Exot. Bot. 2: 109. pl. 114. 1806), but the name P. denticulata has
rightly been kept for the form which Smith described and figured under this name.

Hemerocallis lilio-asphodelus L. (Sp. Pl. 324. 1753) was originally treated by Linnaeus as
consisting of two varieties: α flava [sphalm. ‘flavus’] and β fulva [sphalm. ‘fulvus’]. In the
second edition of Sp. Pl. (1762) he recognized these as distinct species, calling them H. flava
and H. fulva. However, the original specific epithet must be reinstated for one of these; this
was done by Farwell (Am. Midl. Nat. 11: 51. 1928) and the two species are correctly named
H. lilio-asphodelus L. and H. fulva (L.) L.

The same rule applies to infraspecific taxa, for example, to a subspecies divided
into two or more subspecies, or to a variety divided into two or more varieties.

Section 2. RETENTION OF EPITHETS OF TAXA BELOW THE RANK OF GENUS

ON TRANSFERENCE TO ANOTHER GENUS OR SPECIES

Article 54

When a subdivision of a genus * is transferred to another genus or placed under
another generic name for the same genus without change of rank, its epithet must
be retained or, if it has not been retained, must be reinstated unless one of the
following obstacles exists:

(1) The resulting combination has been previously and validly published for a
subdivision of a genus based on a different type;

(2) An earlier and legitimate epithet of the same rank is available (but see Arts.
13f, 58, 59);

(3) Arts. 21 or 22 provide that another epithet be used.

Examples: Saponaria sect. Vaccaria DC. when transferred to Gypsophila becomes Gypso-
phila sect. Vaccaria (DC.) Godr.

Primula sect. Dionysiopsis Pax when transferred to the genus Dionysia cannot become
Dionysia sect. Dionysiopsis (Pax) Melchior because of Art. 21; the name Dionysia sect.
Ariadna Wendelbo, based on the same type, has to be used instead.

———————

* Here and elsewhere in this Code the phrase “subdivision of a genus” refers only to taxa
between genus and species in rank.

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Article 55

When a species is transferred to another genus or placed under another generic
name for the same genus without change of rank, the specific epithet, if legitimate,
must be retained a or, if it has not been retained, must be reinstated b unless one
of the following obstacles exists:

(1) The resulting binary name is a later homonym c (Art. 64) or a tautonym d
(Art. 23);

(2) An earlier legitimate specific epithet is available (but see Arts. 13f, 58, 59,
72). e

Examples: (a) Antirrhinum spurium L. (Sp. Pl. 613. 1753) when transferred to the genus
Linaria must be called Linaria spuria (L.) Mill. (Gard. Dict. ed. 8. no. 15. 1768).

(b) Spergula stricta Sw. (1799) when transferred to the genus Arenaria must be called
Arenaria uliginosa Schleich. ex Schlechtend. (1808) because of the existence of the name
Arenaria stricta Michx. (1803), referring to a different species; but on further transfer to
the genus Minuartia the epithet stricta must be reinstated and the species called Minuartia
stricta (Sw.) Hiern (1899).

(c) Spartium biflorum Desf. (1798) when transferred to the genus Cytisus by Spach in
1849 could not be called C. biflorus, because this name had been previously and validly
published for a different species by L’Héritier in 1791; the name C. fontanesii given by Spach
is therefore legitimate.

(d) Pyrus malus L. (1753) when transferred to the genus Malus must be called Malus
pumila Mill. (1768), the combination Malus malus (L.) Britton (1913) being inadmissible.

(e) Melissa calamintha L. (1753) when transferred to the genus Thymus becomes T.
calamintha (L.) Scop. (1772); placed in the genus Calamintha it cannot be called C. cala-
mintha (a tautonym) but is called C. officinalis Moench (1794). However, when C. officinalis
is transferred to the genus Satureja, the earlier legitimate epithet is again available and its
name becomes S. calamintha (L.) Scheele (1843).

When, on transference to another genus, the specific epithet has been applied
erroneously in its new position to a different species, the new combination must be
retained for the species to which the epithet was originally applied, and must be
attributed to the author who first published it f. (See Art. 7; par. 9.)

Example: (f) Pinus mertensiana Bong. was transferred to the genus Tsuga by Carrière,
who, however, as is evident from his description, erroneously applied the new combination
Tsuga mertensiana to another species of Tsuga, namely T. heterophylla (Raf.) Sargent: the
combination Tsuga mertensiana (Bong.) Carr. must not be applied to T. heterophylla (Raf.)
Sargent but must be retained for Pinus mertensiana Bong. when that species is placed in
Tsuga; the citation in parentheses (under Art. 49) of the name of the original author, Bongard,
indicates the type of the epithet.

Article 56

When an infraspecific taxon is transferred without change of rank to another
genus or species, the original epithet must be retained or, if it has not been retained,
must be reinstated unless one of the following obstacles exists:

(1) The resulting ternary combination has been previously and validly published
for an infraspecific taxon based on a different type, even if that taxon is of different
rank;

(2) An earlier legitimate epithet is available (but see Arts. 13f, 58, 59, 72);

(3) Arts. 24 or 26 provide that another epithet be used.

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Example: The variety micranthum Gren. et Godr. (Fl. France 1: 171. 1847) of Helian-
themum italicum Pers. when transferred as a variety to H. penicillatum Thib. retains its
varietal epithet, becoming H. penicillatum var. micranthum (Gren. et Godr.) Grosser (Pflan-
zenreich, Heft 14 (IV. 193): 115. 1903).

When, on transference to another genus or species, the epithet of an infraspecific
taxon has been applied erroneously in its new position to a different taxon of the
same rank, the new combination must he retained for the taxon to which the original
combination was applied, and must be attributed to the author who first published it
(See Art. 7; par. 9).

Section 3. CHOICE OF NAMES WHEN TAXA OF THE SAME RANK ARE

UNITED

Article 57

When two or more taxa of the same rank are united, the oldest legitimate name
or (for taxa below the rank of genus) the oldest legitimate epithet is retained, unless
a later name or epithet must be accepted under the provisions of Arts. 13f, 22, 26,
58, or 59. The author who first unites taxa bearing names or epithets of the same
date has the right to choose one of them, and his choice must be followed.

Examples: K. Schumann (in Engler et Prantl, Nat. Pflanzenfam. III. 6: 5. 1890), uniting
the three genera Sloanea L. (1753), Echinocarpus Blume (1825), and Phoenicosperma Miq.
(1865), rightly adopted the oldest of these three generic names, Sloanea L., for the resulting
genus.

If the two genera Dentaria L. (Sp. Pl. 653. 1753; Gen. Pl. ed. 5. 295. 1754) and Cardamine
L. (Sp. Pl. 654. 1753; Gen. Pl. ed. 5. 295. 1754) are united, the resulting genus must be
called Cardamine because the name was chosen by Crantz (Class. Crucif. 126. 1769), who
was the first to unite the two genera.

Robert Brown (in Tuckey, Narr. Exp. Congo 484. 1818) appears to have been the first
to unite Waltheria americana L. (Sp. Pl. 673. 1753) and W. indica L. (Sp. Pl. 673. 1753).
He adopted the name W. indica for the combined species, and this name is accordingly to
be retained.

Fiori et Paoletti (Fl. Ital. 1(1): 107. 1896) united Triticum aestivum L. (Sp. Pl. 85. 1753)
and T. hybernum L. (Sp. Pl. 85. 1753) into one species under one of these names, T. aestivum
L. Consequently the latter name is correct for the combined taxon comprising common soft
wheat. The use of an illegitimate name, such as Triticum vulgare Vill. (Hist. Pl. Dauph. 2:
153. 1787), or the creation of a new name is contrary to the Code.

Baillon (Adansonia 3: 162. 1862-1863), when uniting for the first time Sclerocroton
integerrimus Hochst. ex Krauss (Flora 28: 85. 1845) and Sclerocroton reticulatus Hochst. ex
Krauss (Flora 28: 85. 1845) adopted the first epithet for the combined taxon. Consequently
this epithet is to be retained irrespective of the generic name (Sclerocroton, Stillingia, Ex-
coecaria, Sapium) to which it is attached.

Linnaeus in 1753 (Sp. Pl. 902) simultaneously published the names Verbesina alba and V.
prostrata. Later (Mant. 286. 1771), he published Eclipta erecta, a superfluous name because
V. alba is cited in synonymy, and E. prostrata, based on V. prostrata. However, the first
author to unite these taxa was Hasskarl (Pl. Jav. Rar. 528. 1848), who did so under the name
Eclipta alba (L.) Hassk., which therefore is to be used if these taxa are united and placed
in the genus Eclipta.

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Recommendation 57A

Authors who have to choose between two generic names should note the following
suggestions:

(1) Of two names of the same date, to prefer that which was first accompanied by the
description of a species.

(2) Of two names of the same date, both accompanied by descriptions of species, to
prefer that which, when the author makes his choice, includes the larger number of species.

(3) In cases of equality from these various points of view, to select the more appropriate
name.

Article 58

When a taxon of recent plants, algae excepted, and a taxon of the same rank of
fossil or subfossil plants are united, the correct name or epithet of the recent taxon
takes precedence.

Example: If Platycarya Sieb. et Zucc. (1843), a genus of recent plants, and Petrophiloides
Bowerbank (1840), a genus of fossil plants, are united, the name Platycarya is accepted for
the combined genus, although it is antedated by Petrophiloides.

Section 4. NAMES OF FUNGI WITH A PLEOMORPHIC LIFE CYCLE AND

OF FOSSILS ASSIGNED TO FORM-GENERA

Article 59

In Ascomycetes and Basidiomycetes (inclusive of Ustilaginales) with two or more
states in the life cycle (except those which are lichen-fungi), the correct name of
all states which are states of any one species is the earliest legitimate name typified
by the perfect state. The perfect state is that which is characterized by the presence
of asci in the Ascomycetes, cells of the kind giving rise to basidia in the Uredinales
and in the Ustilaginales, or basidia or organs which bear basidia in the other
orders of the Basidiomycetes. However, the provisions of this Article shall not be
construed as preventing the use of names of imperfect states in works referring to
such states; in the case of imperfect states, a name refers only to the state
represented by its type.

When not already available, specific or infraspecific names for imperfect states
may be proposed at the time of publication of the name for a perfect state or later,
and may contain either the specific epithet applied to the perfect state or any other
epithet available.

The nomenclatural type of a taxon whose name has been ascribed to a genus
characterised by a perfect state must be one of which the original description or
diagnosis included a description or diagnosis of the perfect state (or of which the
possibility cannot be excluded that the original author included the perfect state in
his description or diagnosis). If these requirements are not fulfilled the name,
although validly published, shall be considered illegitimate.

The combination of the specific or infraspecific epithet of a name typified by
an imperfect state with a name of a genus characterised by a perfect state shall be
considered not validly published as a new combination, but shall be considered
the validly published name of a new taxon if the author provides a description (in
Latin, on or after 1 Jan. 1935) of the perfect state and indicates a type (on or after
1 Jan. 1958) showing the perfect state, and shall be attributed to the author of
that name and to him alone. However, publication on or after 1 Jan. 1967 of a

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combination based on an imperfect state and applied inclusive of the perfect state
shall not be considered the valid publication of a new name of the perfect state.

Examples: The name Ravenelia cubensis Arth. & J. R. Johnston (Mem. Torrey Bot. Club
17: 118. 1918), based on a specimen bearing only uredia (an imperfect state), was validly
published but is considered illegitimate because the species concerned was described in a
genus characterised by a perfect state. The correct name is Uredo cubensis Cummins
(Mycologia 48: 607. 1956), published as ‘(Arth. & J. R. Johnston) Cumm. comb. nov.’ (see
Art. 72).

The combination ‘Mycosphaerella aleuritidis (Miyake) Ou nov. comb. (Sinensia 11: 183.
1940), syn. Cercospora aleuritidis Miyake’, published with a Latin diagnosis of the perfect
state, is considered not validly published as a new combination (since the type of the basionym
does not bear the perfect state) but validly published as a new name of a new species, which
is cited as ‘M. aleuritidis Ou’, based on the material examined by Ou which bore the perfect
state. Since this is an undesirable method of publishing the name of a new taxon, a name
published in this manner on or after 1 Jan. 1967 is not validly published either as a new
combination or as a new name of a new taxon. The correct method of publication of this
name would be ‘Mycosphaerella aleuritidis Ou, syn. Cercospora aleuritidis Miyake’, though
it is not essential (for the purposes of nomenclature) that the synonymy be mentioned, and
Ou could equally well have chosen any available epithet other than aleuritidis.

Corticium microsclerotia (Matz) Weber, nov. comb., syn. Rhizoctonia microsclerotia Matz,
was published (Phytopathology 29: 565. 1939) with a description in English of the perfect
state drawn up from a specimen different from the type of Rhizoctonia microsclerotia Matz.
Weber’s combination is nevertheless considered to be based on Matz’s type of Rhizoctonia
microsclerotia and is considered not validly published because this type does not show the
characteristics of a perfect state genus. The name is likewise not validly published as a new
name of a new taxon based on Weber’s material, because no Latin diagnosis was provided.
The correct name for this species is Corticium microsclerotia Weber (Mycologia 43: 728. 1951,
where a Latin diagnosis was supplied for the perfect state: the epithet microsclerotia was not
preoccupied in Corticium).

As in the case of pleomorphic fungi, the provisions of the Code shall not be
construed as preventing the use of names of form-genera in works referring to
such taxa.

Section 5. CHOICE OF NAMES WHEN THE RANK OF A TAXON IS CHANGED

Article 60

When the rank of a genus or infrageneric * taxon is changed, the correct name or
epithet is the earliest legitimate one available in the new rank. In no case does a
name or an epithet have priority outside its own rank.

Examples: The section Campanopsis R. Br. (Prodr. 561. 1810) of the genus Campanula
was first raised to generic rank by Schrader and, as a genus, is called Wahlenbergia Schrad.
ex Roth (Nov. Pl. Sp. 399. 1821), not Campanopsis (R. Br.) O. Kuntze (Rev. Gen. Pl. 2: 378.
1891).

Magnolia virginiana var. foetida L. (Sp. Pl. 536. 1753) when raised to specific rank is
called Magnolia grandiflora L. (Syst. Nat. ed. 10. 1082. 1759), not M. foetida (L.) Sargent
(Gard. & For. 2: 615. 1889).

———————

* Here and elsewhere in the Code the term ‘infrageneric’ refers to all ranks below that
of genus.

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Lythrum intermedium Ledeb. (Ind. Hort. Dorpat 1822) when treated as a variety of
Lythrum salicaria L. (1753), is called L. salicaria var. glabrum Ledeb. (Fl. Ross. 2: 127. 1843),
not L. salicaria var. intermedium (Ledeb.) Koehne (Bot. Jahrb. 1: 327. 1881).

In all these cases, the name or epithet given to the taxon in its original rank is replaced
by the first correct name or epithet given to it in its new rank.

Recommendation 60A

(1) When a section or a subgenus is raised in rank to a genus, or the inverse change
occurs, the original name or epithet should be retained unless it is contrary to this Code.

(2) When an infraspecific taxon is raised in rank to a species, or the inverse change occurs,
the original epithet should be retained unless the resulting combination is contrary to this
Code.

(3) When an infraspecific taxon is changed in rank within the species, the original
epithet should be retained unless the resulting combination is contrary to this Code.

Article 61

When a taxon of a rank higher than genus and not higher than family is changed
in rank, the stem of the name is to be retained and only the termination altered
(-inae, -eae, -oideae, -aceae), unless the resulting name is rejected under Arts. 62—72.

Example: The subtribe Drypetinae Pax (1890) (Euphorbiaceae) when raised to the rank
of tribe becomes Drypeteae (Pax) Hurusawa (1954); the subtribe Antidesmatinae Pax (1890)
(Euphorbiaceae) when raised to the rank of subfamily becomes Antidesmatoideae (Pax)
Hurusawa (1954).

Section 6. REJECTION OF NAMES AND EPITHETS

Article 62

A legitimate name or epithet must not be rejected merely because it is inappropriate
or disagreeable, or because another is preferable or better known, or because it has
lost its original meaning.

Examples: The following changes are contrary to the rule: Staphylea to Staphylis, Tamus
to Thamnos, Thamnus, or Tamnus, Mentha to Minthe, Tillaea to Tillia, Vincetoxicum to Alexi-
toxicum; and Orobanche rapum to O. sarothamnophyta, O. columbariae to O. columbarihaerens,
O. artemisiae to O. artemisiepiphyta. All these modifications are to rejected.

Ardisia quinquegona Blume (1825) is not to be changed to A. pentagona A. DC. (1834),
although the specific epithet quinquegona is a hybrid word (Latin and Greek) (see Rec.
23B, c). — The name Scilla peruviana L. (Sp. Pl. 309. 1753) is not to be rejected because
the species does not grow in Peru. — The name Petrosimonia oppositifolia (Pall.) Litw.,
based on Polycnemum oppositifolium Pall. (Reise 1: 422, 431, app. 484. 1771), is not to be
rejected because the species has leaves only partly opposite, and partly alternate, although
there is another closely related species, Petrosimonia brachiata (Pall.) Bunge, having all its
leaves opposite.

Richardia L. (1753) is not to be changed to Richardsonia, as was done by Kunth (Mém.
Mus. Hist. Nat. [Paris] 4: 430. 1818), although the name was originally dedicated to the
British botanist, Richardson.

The names of species and of subdivisions of genera assigned to genera whose names
are conserved later homonyms, and which had earlier been assigned to the genera
under the rejected homonymic names, are legitimate under the conserved names

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without change of authorship or date if there is no other obstacle under the rules.

Example: Alpinia languas Gmel. (1791) and Alpinia galanga (L.) Willd. (1797) are to be
accepted although Alpinia L. (1753), to which they were assigned by their authors, is rejected
and the genus in which they are now placed is Alpinia Roxb. (1810), nom. cons.

Article 63

A name is illegitimate and is to be rejected if it was nomenclaturally superfluous
when published, i.e. if the taxon to which it was applied, as circumscribed by its
author, included the type of a name or epithet which ought to have been adopted
under the rules.

The inclusion of a type (see Art. 7) is here understood to mean the citation of a
type specimen, the citation of the illustration of a type specimen, the citation of the
type of a name, or the citation of the name itself unless the type is at the same time
excluded either explicitly or by implication.

Examples of superfluous names: The generic name Cainito Adans. (Fam. 2: 166. 1763) is
illegitimate because it was a superfluous name for Chrysophyllum L. (Sp. Pl. 192. 1753); the
two genera had precisely the same circumscription.

Chrysophyllum sericeum Salisb. (Prodr. 138. 1796) is illegitimate, being a superfluous
name for C. cainito L. (1753), which Salisbury cited as a synonym.

Picea excelsa (Lam.) Link is illegitimate, because it is based on Pinus excelsus Lam. (Fl.
Franç. 2: 202. 1778), a superfluous name for Pinus abies L. (Sp. Pl. 1002. 1753). Under
Picea the proper name is Picea abies (L.) Karst. (Deutschl. Fl. 325. 1880).

On the other hand, Cucubalus latifolius Mill. and C. angustifolius Mill. (Gard. Dict. ed. 8.
nos. 2, 3. 1768) are not illegitimate names, although these species are now reunited with
C. behen L. (1753), from which Miller separated them: C. latifolius Mill. and C. angustifolius
Mill. as circumscribed by Miller did not include the type of C. behen L.

Example of explicit exclusion of type: When publishing the name Galium tricornutum,
Dandy (Watsonia 4: 47. 1957) cited G. tricorne Stokes (1787) pro parte as a synonym, but
explicitly excluded the type of the latter name.

Examples of exclusion of type by implication: Cedrus Duhamel (Trait. Arbr. 1: xxviii, 139.
t. 52. 1755) is a legitimate name even though Juniperus L. was cited as a synonym; only
some of the species of Juniperus L. were included in Cedrus and the differences between the
two genera are discussed, Juniperus (including its type species) being recognized in the same
work as an independent genus.

Tmesipteris elongata Dangeard (Le Botaniste 2: 213. 1890-91) was published as a new
species but Psilotum truncatum R. Br. was cited as a synonym. However, on the following
page (214), T. truncata (R. Br.) Desv. is recognized as a different species and on p. 216 the
two are distinguished in a key, thus showing that the meaning of the cited synonym was
either “P. truncatum R. Br. pro parte” or “P. truncatum auct. non R. Br.”

Solanum torvum Swartz (Prodr. 47. 1788) was published with a new diagnosis but S.
indicum L. (Sp. Pl. 187. 1753) was cited as a synonym. In accord with the practice in his
Prodromus, Swartz indicated where the species was to be inserted in the latest edition [14,
Murray] of the Systema Vegetabilium. S. torvum was to be inserted between species 26 (S.
insanum) and 27 (S. ferox); the number of S. indicum in this edition of the Systema is 32.
S. torvum is thus a legitimate name; the type of S. indicum is excluded by implication.

A name is not illegitimate, even if it was nomenclaturally superfluous when pub-
lished, if it is a new combination the epithet of whose basionym is legitimate. When
published it is incorrect, but it may become correct later.

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Example: Chloris radiata (L.) Sw. (Prodr. 26. 1788), based on Agrostis radiata L. (Syst.
Nat. ed. 10. 2: 873. 1759), was nomenclaturally superfluous when published, since Swartz
also cited Andropogon fasciculatum L. (Sp. Pl. 1047. 1753) as a synonym. It is, however,
the correct name in the genus Chloris for Agrostis radiata when Andropogon fasciculatum
is treated as a different species, as was done by Hackel (in DC. Monogr. Phan. 6: 177. 1889).

Article 64

A name is illegitimate and must be rejected if it is a later homonym, that is, if it
is spelled exactly like a name previously and validly published for a taxon of the
same rank based on a different type. Even if the earlier homonym is illegitimate,
or is generally treated as a synonym on taxonomic grounds, the later homonym
must be rejected, unless it has been conserved.

Note. Mere orthographic variants of the same name are treated as homonyms
when they are based on different types (see Arts. 73 and 75).

Examples: The name Tapeinanthus Boiss. ex Benth. (1848), given to a genus of Labiatae,
is a later homonym of Tapeinanthus Herb. (1837), a name previously and validly published
for a genus of Amaryllidaceae; Tapeinanthus Boiss. ex Benth. is therefore rejected, as was
done by Th. Durand (Ind. Gen. Phan. x. 1888), who renamed it Thuspeinanta.

The generic name Amblyanthera Müll. Arg. (1860) is a later homonym of the validly
published generic name Amblyanthera Blume (1849) and is therefore rejected, although
Amblyanthera Blume is now considered to be a synonym of Osbeckia L. (1753).

The name Torreya Arnott (1838) is a nomen conservandum (see Art. 14) and is therefore
not to be rejected because of the existence of the earlier homonym Torreya Rafinesque (1818).

Astragalus rhizanthus Boiss. (Diagn. Pl. Orient. 2: 83. 1843) is a later homonym of the
validly published name Astragalus rhizanthus Royle (Ill. Bot. Himal. 200. 1835) and it is
therefore rejected, as was done by Boissier, who renamed it A. cariensis (Diagn. Pl. Orient.
9: 56. 1849).

The names of two subdivisions of the same genus, or of two infraspecific taxa
within the same species, even if they are of different rank, are treated as homonyms
if they have the same epithet and are not based on the same type. The same epithet
may be used for subdivisions of different genera, and for infraspecific taxa within
different species.

Examples: Under Verbascum the sectional epithet Aulacosperma Murbeck (1933) is allowed,
although there was already in the genus Celsia a section named Aulacaspermae Murbeck
(1926). This, however, is not an example to be followed, since it is contrary to Rec. 21B,
paragraph 3.

The following is illegitimate: Erysimum hieraciifolium subsp. strictum var. longisiliquum
and E. hieraciifolium subsp. pannonicum var. longisiliquum — two varieties may not bear
the same epithet in the same species.

The name Andropogon sorghum subsp. halepensis (L.) Hackel var. halepensis is legitimate,
since the subspecies and the variety have the same type and the epithet may be repeated
under Rec. 26A.

When the same new name is simultaneously published for more than one taxon,
the first author who adopts it in one sense, rejecting the other, or provides another
name for one of these taxa is to be followed.

Example: Linnaeus simultaneously published both Mimosa 10 cinerea (Sp. Pl. 517. 1753)
and Mimosa 25 cinerea (Sp. Pl. 520. 1753). Later, he (Syst. Nat., ed. 10. 2: 1311. 1759)
renamed species 10 Mimosa cineraria and retained the name Mimosa cinerea for species 25;
Mimosa cinerea is thus the legitimate name for species 25.

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Article 65

A name is illegitimate and is to be rejected if it is the name of a taxon which
on transfer of that taxon from the animal to the plant kingdom becomes, at the
time of such transfer, a homonym of a name for a plant taxon.

If a taxon is transferred from the plant kingdom to the animal kingdom, its name
or names retain their status in botanical nomenclature for purposes of homonymy.
In all other cases, the name of a plant is not to be rejected merely because it is
the same as the name of an animal.

Article 66

An epithet of a subdivision of a genus is illegitimate and is to be rejected in the
following special cases:

(1) If it was published in contravention of Arts. 51, 54, 57, 58 or 60, i.e. if its
author did not adopt the earliest legitimate epithet available for the taxon with
its particular circumscription, position, and rank.

(2) If it is an epithet of a type subgenus or section which contravenes Art. 22.

Note 1. Illegitimate epithets are not to be taken into consideration for purposes
of priority (see Art. 45) except in the rejection of a later homonym (Art. 64).

Note 2. An epithet originally published as part of an illegitimate name may be
adopted later for the same taxon, but in another combination (see Art. 72).

Article 67

A specific or infraspecific epithet is illegitimate and is to be rejected if it was
published in contravention of Arts. 51, 53, 55, 56, or 60, i.e. if its author did not
adopt the earliest legitimate epithet available for the taxon with its particular circum-
scription, position, and rank. Such an epithet is also illegitimate if it was published
in contravention of Art. 59.

Note. The publication of a name containing an illegitimate epithet is not to be
taken into consideration for purposes of priority (see Art. 45) except in the rejection
of a later homonym (Art. 64).

Article 68

A specific epithet is not illegitimate merely because it was originally published
under an illegitimate generic name, but is to be taken into consideration for purposes
of priority if the epithet and the corresponding combination are in other respects
in accordance with the rules. In the same way an infraspecific epithet may be
legitimate even if originally published under an illegitimate name of a species or
infraspecific taxon.

Example: Agathophyllum A. L. Juss. (Gen. Pl. 431. 1789) is an illegitimate generic name,
being a superfluous substitute for Ravensara Sonnerat (Voy. Ind. Or. 2: 226. 1782). Never-
theless the epithet of the validly published name Agathophyllum neesianum Blume (Mus.
Bot. Lugd. Bat. 1: 339. 1851) is legitimate. Because Meisner cited Agathophyllum neesianum
as a synonym of Mespilodaphne mauritiana Meisn. (in DC., Prodr. 15(1): 104. 1864) but did
not adopt its epithet, M. mauritiana is a superfluous name and hence illegitimate.

Note. An illegitimate epithet may be adopted later for the same taxon, but in
another combination (see Art. 72).

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Article 69

A name is to be rejected if it is used in different senses and so has become a
long-persistent source of error.

Examples: Linnaeus (Sp. Pl. 145. 1753) included all the European and western Asiatic
Cyclamen species under the name C. europaeum. The name was first restricted to one species
by Miller (Gard. Dict. ed. 8. 1768) and later to a different species by Jacquin (Fl. Austr. 5: 1.
t. 401. 1778) and Aiton (Hort. Kew. 1: 196. 1789). Both interpretations have been followed,
with a great preponderance in favour of the later, incorrect application. The name Cyclamen
europaeum has thus become a long-persistent source of error and is to be rejected.

Lavandula spica L. (Sp. Pl. 572. 1753) included the two species subsequently known as
L. angustifolia Mill. and L. latifolia Vill. The name Lavandula spica has been applied almost
equally to these two species, and, being now ambiguous, is rejected (see Kew Bull. 1932: 295).

Article 70

A name is to be rejected if it is based on a type consisting of two or more entirely
discordant elements, unless it is possible to select one of these elements as a satis-
factory type.

Examples: The characters of the genus Schrebera L. (Sp. Pl. ed. 2. 1662. 1763; Gen. Pl.
ed. 6. 124. 1764) were derived from the two genera Cuscuta and Myrica (parasite and host)
(see Retz. Obs. 6: 15. 1791). The characters of the genus Actinotinus Oliv. (Hook. Ic. Pl.
pl. 1740. 1888) were derived from the two genera Viburnum and Aesculus, owing to the
insertion of the inflorescence of a Viburnum in the terminal bud of an Aesculus by a collector.
The names Schrebera L. and Actinotinus Oliv. are therefore abandoned.

The name of the genus Pouteria Aubl. (Pl. Guiane 85. 1775) is based on a type which
is a mixture of a species of Sloanea (Elaeocarpaceae) and a sapotaceous species (flowers and
leaves); both elements can be easily separated, as has been done by Martius, and Radlkofer
was correct in proposing (Sitzber. Math.-Phys. Cl. Bayer. Akad. München 12: 333. 1882) to
retain the name Pouteria for the part of the type belonging to the Sapotaceae.

Article 71

A name is to be rejected if it is based on a monstrosity.

Examples: The generic name Uropedium Lindl. (Orch. Linden. 28. 1846) was based on
a monstrosity which is now referred to Phragmipedium caudatum (Lindl.) Rolfe (Orchid
Rev. 4: 330. 1896); it is therefore rejected.

The name Ornithogalum fragiferum Vill. (Hist. Pl. Dauph. 2: 270. 1787) was based on
a monstrosity and is therefore rejected.

Article 72

A name or epithet rejected under Arts. 63—71 is replaced by the oldest legitimate
name or (in a combination) by the oldest available legitimate epithet in the rank
concerned. If none exists in any rank a new name must be chosen: a) a new name
(nomen novum) based on the same type as the rejected name may be published, or
b) a new taxon may be described and a new name published for it. If a name or
epithet is available in another rank, one of the above alternatives may be chosen or
c) a new combination, based on the name in the other rank, may be published.
Similar action is to be taken when the use of an epithet is inadmissible under Arts. 21,
23, and 24.

Example: Linum radiola L. (1753) when transferred to the genus Radiola must not be
called Radiola radiola (L.) H. Karst. (1882), as that combination is inadmissible under Art. 23.

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The next oldest specific epithet is multiflorum, but the name Linum multiflorum Lam. (1778)
is illegitimate, since it was a superfluous name for L. radiola L.; under Radiola, the species
is to be called R. linoides Roth (1788), since linoides is the oldest legitimate specific epithet
available.

Note. When a new epithet is required, an author may adopt an epithet previously
given to the taxon in an illegitimate name if there is no obstacle to its employment
in the new position or sense; the epithet in the resultant combination is treated
as new.

Example: The name Talinum polyandrum Hook. (Bot. Mag. pl. 4833. 1855) is illegitimate,
being a later homonym of T. polyandrum Ruiz & Pav. (Syst. 1: 115. 1798); when Bentham
transferred T. polyandrum Hook. to Calandrinia, he called it Calandrinia polyandra (Fl.
Austr. 1: 172. 1863). The epithet polyandra in this combination is treated as new, dating
from 1863, and the binomial should be written Calandrinia polyandra Benth., not C. poly-
andra (Hook.) Benth.

Recommendation 72A

Authors should avoid adoption of an illegitimate epithet previously published for the
same taxon.

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Chapter VI. ORTHOGRAPHY OF NAMES AND EPITHETS AND GENDER

OF GENERIC NAMES

Section 1. ORTHOGRAPHY OF NAMES AND EPITHETS

Article 73

The original spelling of a name or epithet is to be retained, except for the correction
of typographic or orthographic errors (but see Art. 14, note 7).

Note 1. The words “original spelling” in this Article mean the spelling employed
when the name was validly published. They do not refer to the use of an initial capital
or small letter, this being a matter of typography (see Art. 21, Rec. 73F).

Note 2. The liberty of correcting a name is to be used with reserve, especially
if the change affects the first syllable and, above all, the first letter of the name.

The consonants w and y, foreign to classical Latin, and k, rare in that language,
are permissible in Latin plant names.

The letters j and v are to be changed to i and u respectively when they represent
vowels; the reverse changes are to be made when consonants are required.

Examples: Taraxacvm Zinn is to be changed to Taraxacum, Iungia L. f. to Jungia, Saurauja
Willd. to Saurauia, subgenus Nevropteris Brongniart to Neuropteris.

Diacritic signs are not used in Latin plant names. In names (either new or old)
drawn from words in which such signs appear, the signs are to be suppressed with
the necessary transcription of the letters so modified; for example ä, ö, ü become
respectively ae, oe, ue; é, è, ê become e, or sometimes ae; ñ becomes n; ø becomes
oe; å becomes ao; the diaeresis, however, is permissible (Cephaëlis for Cephaelis).*

When changes made in orthography by earlier authors who adopt personal,
geographic, or vernacular names in nomenclature are intentional latinizations, they
are to be preserved.

The use of a wrong connecting vowel or vowels (or the omission of a connecting
vowel) in a name or an epithet is treated as an orthographic error (see Rec. 73G).

The wrong use of the terminations i, ii, ae, iae, anus, or ianus, mentioned in Rec.
73C (a, b, d), is treated as an orthographic error.

Examples of retention of original spelling: The generic names Mesembryanthemum L.
(1753) and Amaranthus L. (1753) were deliberately so spelled by Linnaeus and the spelling
is not to be altered to Mesembrianthemum and Amarantus respectively, although these latter
forms are philologically preferable (see Kew Bull. 1928: 113, 287).

Valantia L. (1753), Gleditsia L. (1753), and Clutia L. (1753), commemorating Vaillant,
Gleditsch and Cluyt respectively, are not to be altered to Vaillantia, Gleditschia and Cluytia **:

———————

* The diaeresis should be used where required in works in which diphthongs are not
represented by special type, e.g. Cephaëlis in works in which there is Arisaema, not
Arisæma.

** In some cases an altered spelling of a generic name is conserved e.g. Bougainvillea (see
list of nomina conservanda no. 2350).

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Linnaeus latinized the names of these botanists deliberately as “Valantius”, “Gleditsius”, and
“Clutius”.

Phoradendron Nutt. is not to be altered to Phoradendrum.

Triaspis mozambica Adr. Juss. is not to be altered to T. mossambica, as in Engler Pflan-
zenw. Ost-Afr. C: 232 (1895).

Alyxia ceylanica Wight is not to be altered to A. zeylanica, as in Trimen, Handb. Fl. Ceyl.
3: 127 (1895).

Fagus sylvatica L. is not to be altered to F. silvatica. The correct classical spelling silvatica
is recommended for adoption in the case of a new name (Rec. 73E), but the mediaeval
spelling sylvatica, deliberately adopted by Linnaeus, is not to be altered.

The spelling of the generic name Lespedeza is not to be altered, although it commemo-
rates Vicente Manuel de Céspedes (see Rhodora 36: 130-132, 390-392. 1934).

Examples of typographic errors: Globba brachycarpa Baker (in Hook. f., Fl. Brit. lnd. 6:
205. 1890) and Hetaeria alba Ridley (Journ. Lirm. Soc. Bot. 32: 404. 1896) are typographic
errors for Globba trachycarpa Baker and Hetaeria alta Ridley respectively (see Journ. of Bot.
59: 349. 1921). – Thevetia nereifolia Adr. Juss. ex Steud. is an obvious typographic error
for T. neriifolia.

Example of an orthographic error: Gluta benghas L. (Mant. 293. 1771), being an ortho-
graphic error for G. renghas, should be cited as G. renghas L., as has been done by Engler
(in DC. Monogr. Phan. 4: 225. 1883); the vernacular name used as a specific epithet
by Linnaeus is “Renghas”, not “Benghas”.

Examples of errors treated as orthographic: Pereskia opuntiaeflora DC. (Mém. Mus. Hist.
Nat. Paris 17: 76. 1828) should be cited as P. opuntiiflora DC. (cf. Rec. 73G).

Cacalia napeaefolia DC. (in DC. Prodr. 6: 328. 1837) and Senecio napeaefolius (DC.)
Schultz-Bip. (Flora 28: 498. 1845) should be cited as Cacalia napaeifolia DC. and Senecio
napaeifolius (DC.) Schultz-Bip. respectively; the specific epithet refers to the resemblance
of the leaves to those of the genus Napaea (not Napea), and the reduced stem-ending i
should have been used instead of ae.

Dioscorea lecardi De Wild. should be corrected to D. lecardii, and Berberis wilsonae
Hemsl. should be corrected to B. wilsoniae; the genitive forms derived from Lecard (m) and
Wilson (f) prescribed by Rec. 73C are lecardii and wilsoniae respectively. Artemisia verlotorum
Lamotte should be corrected to A. verlotiorum.

Example of both a typographic and an orthographic error: Rosa pissarti Carr. (Rev. Hort.
1880: 314) is a typographic error for R. pissardi (see Rev. Hort. 1881: 190), which in its turn
is treated as an orthographic error for R. pissardii (see Rec. 73C, b).

Recommendation 73A

When a new name or epithet is to be derived from Greek, the transliteration to Latin
should conform to classical usage.

The spiritus asper should be transcribed in Latin as the letter h.

Recommendation 73B

When a new name for a genus, subgenus, or section is taken from the name of a person,
it should be formed in the following manner:

(a) When the name of the person ends in a vowel, the letter a is added (thus Ottoa
after Otto; Sloanea after Sloane), except when the name ends in a, when ea is added (e.g.
Collaea after Colla), or in ea (as Correa), when no letter is added.

(b) When the name of the person ends in a consonant, the letters ia are added, except
when the name ends in er, when a is added (e.g. Kernera after Kerner). In latinized names
ending in -us, this termination is dropped before adding the suffix (Dillenia).

(c) The syllables not modified by these endings retain their original spelling, unless they
contain letters foreign to Latin plant names or diacritic signs (see Art. 73).

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(d) Names may be accompanied by a prefix or a suffix, or be modified by anagram or
abbreviation. In these cases they count as different words from the original name.

Examples: Durvillea and Urvillea; Lapeirousia and Peyrousea; Englera, Englerastrum, and
Englerella; Bouchea and Ubochea; Gerardia and Graderia; Martia and Martiusia.

Recommendation 73C

When a new specific or infraspecific epithet is taken from the name of a man, it should
be formed in the following manner:

(a) When the name of the person ends in a vowel, the letter i is added (thus glazioui
from Glaziou, bureaui from Bureau, keayi from Keay), except when the name ends in a,
when e is added (thus balansae from Balansa, palhinhae from Palhinha).

(b) When the name ends in a consonant, the letters ii are added (ramondii from Ramond),
except when the name ends in -er, when i is added (thus kerneri from Kerner).

(c) The syllables not modified by these endings retain their original spelling, unless they
contain letters foreign to Latin plant names or diacritic signs (see Art. 73).

(d) When epithets taken from the name of a man have an adjectival form they are
formed in a similar way (e.g. Geranium robertianum, Verbena hasslerana, Asarum hayatanum,
Andropogon gayanus).

(e) The Scottish patronymic prefix ‘Mac’, ‘Mc’ or ‘M’, meaning ‘son of’, should be spelled
‘mac’ and united with the rest of the name, e.g. macfadyenii after Macfadyen, macgillivrayi
after MacGillivray, macnabii after McNab, mackenii after M’Ken.

(f) The Irish patronymic prefix ‘O’ should be united with the rest of the name or omitted, e.g.
obrienii, brienianus after O’Brien, okellyi after O’Kelly.

(g) A prefix consisting of an article, e.g. le, la, 1’, les, el, il, lo, or containing an article,
e.g. du, dela, des, del, della, should be united to the name, e.g. leclercii after Le Clerc,
dubuyssonii after DuBuysson, lafarinae after La Farina, logatoi after La Gato.

(h) A prefix to a surname indicating ennoblement or canonization should be omitted. e.g.
candollei after De Candolle, jussieui after de Jussieu, hilairei after Saint-Hilaire, remyi after
St. Rémy; in geographical epithets, however, ‘St.’ is rendered as sanctus (m.) or sancta (f.)
e.g. sancti-johannis, of St. John, sanctae-helenae, of St. Helena.

(i) A German or Dutch prefix: when it is normally treated as part of the family name, as
often happens outside its country of origin, e.g. in the United States, may be included in
the epithet, e.g. vonhausenii after Vonhausen, vanderhoekii after Vanderhoek, vanbruntiae
after Mrs. Van Brunt, but should otherwise be omitted, e.g. iheringii after von Ihering,
martii after von Martius, steenisii after van Steenis, strassenii after zu Strassen, vechtii after
van der Vecht.

If the personal name is already Latin or Greek, the appropriate Latin genitive should be
used, e.g. alexandri from Alexander, francisci from Franciscus, augusti from Augustus, linnaei
from Linnaeus, hectoris from Hector.

The same provisions apply to epithets formed from the names of women. When these
have a substantival form, they are given a feminine termination (e.g. Cypripedium hookerae,
Rosa beatricis, Scabiosa olgae, Omphalodes luciliae).

Recommendation 73D

An epithet derived from a geographical name is preferably an adjective and usually takes
the termination -ensis, -(a)nus, -inus, -ianus, or -icus.

Examples: Rubus quebecensis (from Quebec), Ostrya virginiana (from Virginia), Polygonum
pensylvanicum (from Pennsylvania).

Recommendation 73E

A new epithet should be written in conformity with the original spelling of the word or

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words from which it is derived and in accordance with the accepted usage of Latin and
latinization (see Art. 23).

Example: sinensis (not chinensis).

Recommendation 73F

All specific and infraspecific epithets should be written with a small initial letter, although
authors desiring to use capital initial letters may do so when the epithets are directly derived
from the names of persons (whether actual or mythical), or are vernacular (or non-Latin)
names, or are former generic names.

Recommendation 73G

A compound name or an epithet combining elements derived from two or more Greek
or Latin words should be formed, as far as practicable, in accordance with classical usage.
This may be stated as follows:

(a) In a true compound (as distinct from pseudocompounds such as Myos-otis, nidus-avis)
a noun or adjective in a non-final position appears as a bare stem without case-ending
(Hydro-phyllum).

(b) Before a vowel the final vowel of this stem, if any, is normally elided (Chrys-
anthemum, mult-angulus), with the exception of Greek y and i (poly-anthus, Meli-osma).

(c) Before a consonant the final vowel is normally preserved in Greek (mono-carpus,
Poly-gonum, Coryne-phorus, Meli-lotus), except that a is commonly replaced by o (Hemero-
callis from hemera); in Latin the final vowel is reduced to i (multi-color, menthi-folius, salvii-
folius).

(d) If the stem ends in a consonant, a connecting vowel (o in Greek, i in Latin) is
inserted before a following consonant (Odont-o-glossum, cruc-i-formis).

Some irregular forms, however, have been extensively used through false analogy (atro-
purpureus, on the analogy of pseudo-compounds such as fusco-venatus in which o is the
ablative case-ending). Others are used as revealing etymological distinctions (caricae-formis
from Carica, as distinct from carici-formis from Carex; tubae-florus, with trumpet-shaped
flowers, as distinct from tubi-florus, with tube-like or tubular flowers). Where such irregulari-
ties occur in the original spelling of existing compounds, this spelling should be retained.

Note. The hyphens in the above examples are given solely for explanatory reasons. For
the use of hyphens in botanical names and epithets see Arts. 20 and 23.

Recommendation 73H

Epithets of fungus names derived from the generic name of the host plant should be
spelled in accordance with the accepted spelling of this name; other spellings must be
regarded as orthographic variants and should be corrected.

Examples: Phyllachora anonicola Chardon (1940) should be altered to P. annonicola, since
the spelling Annona is now accepted in preference to Anona; – Meliola albizziae Hansford
et Deighton (1948) should be altered to M. albiziae, since the spelling Albizia is now
accepted in preference to Albizzia.

Recommendation 73I

The etymology of new names and epithets should be given when the meaning of these
is not obvious.

Article 74

When the spelling of a generic name differs in Linnaeus’ Species Plantarum ed. 1
and Genera Plantarum ed. 5, the correct spelling is determined by the following
regulations:

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(1) If Linnaeus subsequently to 1753-54 consistently adopted one of the spellings,
that spelling is accepted, e.g. Thuja (not Thuya), Prunella (not Brunella).

(2) If Linnaeus did not do so, then the spelling which is more correct philo-
logically is accepted, e.g. Agrostemma (not Agrostema), Euonymus (not Evonymus).

(3) If the two spellings are equally correct philologically, and there is a great
preponderance of usage in favour of one of them, that one is accepted, e.g. Rhodo-
dendron (not Rhododendrum).

(4) If the two spellings are equally correct philologically, and there is not a
great preponderance of usage in favour of one of them, then the spelling that is in
accordance or more nearly in accordance with Recommendations 73A, 73B, and
73G is accepted, e.g. Ludwigia (not Ludvigia), Ortegia (not Ortega).

Article 75

When two or more generic names are so similar that they are likely to be con-
fused *, because they are applied to related taxa or for any other reason, they are
to be treated as variants, which are homonyms when they are based on different
types.

Examples of names treated as orthographic variants: Astrostemma and Asterostemma;
Pleuripetalum and Pleuropetalum; Columella and Columellia, both commemorating Colu-
mella, the Roman writer on agriculture; Eschweilera and Eschweileria; Skytanthus and
Scytanthus.

The three generic names Bradlea Adans., Bradleja Banks ex Gaertn., and Braddleya Vell.,
all commemorating Richard Bradley, must be treated as orthographic variants because one
only can be used without serious risk of confusion.

Examples of names not likely to be confused: Rubia and Rubus; Monochaete and Mono-
chaetum; Peponia and Peponium; Iria and Iris; Desmostachys and Desmostachya; Sym-
phyostemon and Symphostemon; Gerrardina and Gerardiina; Durvillea and Urvillea; Pelto-
phorus (Poaceae) and Peltophorum (Fabaceae).

The same applies to specific epithets within the same genus and to infraspecific
epithets within the same species.

Examples of epithets treated as orthographic variants: chinensis and sinensis; ceylanica
and zeylanica; napaulensis, nepalensis, and nipalensis; polyanthemos and polyanthemus;
macrostachys and macrostachyus; heteropus and heteropodus; poikilantha and poikilanthes;
pteroides and pteroideus; trinervis and trinervius; macrocarpon and macrocarpum; trachy-
caulum and trachycaulon.

Examples of epithets not likely to be confused: Senecio napaeifolius (DC.) Schultz-Bip.
and S. napifolius Macowan are different names, the epithets napaeifolius and napifolius
being derived respectively from Napaea and Napus.

Lysimachia hemsleyana and Lysimachia hemsleyi (see however, Rec. 23A).

Euphorbia peplis L. and E. peplus L.

Section 2. GENDER OF GENERIC NAMES

Recommendation 75A

The gender of generic names should be determined as follows:

———————

* When it is doubtful whether names are sufficiently alike to be confused, they should
be referred to the General Committee.

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(1) A Greek or Latin word adopted as a generic name should retain its gender. When
the gender varies the author should choose one of the alternative genders. In doubtful cases
general usage should be followed. The following names, however, whose classical gender is
masculine, should be treated as feminine in accordance with botanical custom: Adonis,
Diospyros, Strychnos; so also should Orchis and Stachys, which are masculine in Greek and
feminine in Latin. The name Hemerocallis, derived from the Latin and Greek hemerocalles
(n.), although masculine in Linnaeus’ Species Plantarum, should be treated as feminine in
order to bring it into conformity with almost all other generic names ending in -is.

(2) Generic names formed from two or more Greek or Latin words should take the
gender of the last. If the ending is altered, however, the gender should follow it.

Examples of names formed from Greek words: *

Modern compounds ending in -codon, -myces, -odon, -panax, -pogon, -stemon, and other
masculine words should be masculine. The fact that the generic name Andropogon L. was
originally treated as neuter by Linnaeus is immaterial.

Similarly, all modern compounds ending in -achne, -chlamys, -daphne, -mecon, -osma
(the modern transcription of the feminine Greek word osmé) and other feminine words should
be feminine. The fact that Dendromecon Benth. and Hesperomecon E. L. Greene were
originally ascribed the neuter gender is immaterial. An exception should be made in the
case of names ending in -gaster, which strictly speaking ought to be feminine, but which
should be treated as masculine in accordance with botanical custom.

Similarly, all modern compounds ending in -ceras, -dendron, -nema, -stigma, -stoma and
other neuter words should be neuter. The fact that Robert Brown and Bunge respectively
made Aceras and Xanthoceras feminine is immaterial. An exception should be made for
names ending in -anthos (or -anthus) and -chilos (-chilus or -cheilos), which ought to be
neuter, since that is the gender of the greek words anthos and cheilos, but which have
generally been treated as masculine and should have that gender assigned to them.

Examples of compound generic names where the termination of the last word is altered:
Stenocarpus, Dipterocarpus, and all other modern compounds ending in the Greek masculine
carpos (or carpus), e.g. Hymenocarpos, should be masculine. Those in -carpa or -carpaea
however, should be feminine, e.g. Callicarpa and Polycarpaea; and those in -carpon, -carpum,
or -carpium should be neuter, e.g. Polycarpon, Ormocarpum, and Pisocarpium.

(3) Arbitrarily formed generic names or vernacular names or adjectives used as generic
names, whose gender is not apparent, should take the gender assigned to them by their
authors. Where the original author has failed to indicate the gender, the next subsequent
author may choose a gender, and his choice should be accepted.

Examples: Taonabo Aubl. (Pl. Guiane 569. 1775) should be feminine: Aublet’s two species
were T. dentata and T. punctata.

Agati Adans. (Fam. 2: 326. 1763) was published without indication of gender: the feminine
gender was assigned to it by Desvaux (Journ. Bot. Agric. 1: 120. 1813), who was the first
subsequent author to adopt the name, and his choice should be accepted.

Boehmer (in Ludwig, Def. Gen. Pl. ed. 3. 436. 1760) and Adanson (Fam. 2: 356. 1763)
failed to indicate the gender of Manihot: the first author to supply specific epithets was
Crantz (lnst. Rei Herb. 1: 167. 1766), who proposed the names Manihot gossypiifolia, etc.,
and Manihot should therefore be treated as feminine.

Cordyceps Link (Handb. 3: 346. 1833) is adjectival in form and has no classical gender;
Link assigned to it C. capitatus, etc. and Cordyceps should therefore be treated as masculine.

(4) Generic names ending in -oides or -odes should be treated as feminine irrespective
of the gender assigned to them by the original author.

Recommendation 75B

When a genus is divided into two or more genera, the gender of the new generic name
or names should be that of the generic name that is retained.

Example: When Boletus is divided, the gender of the new generic names should be
masculine: Xerocomus, Boletellus, etc.

———————

* Examples of names formed from Latin words are not given as these offer few difficulties.

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Division I I I . Provisions for modification of the Code

Provision 1. Modification of the Code. The Code may be modified only by
action of a plenary session of an International Botanical Congress on a resolution
moved by the Nomenclature Section of that Congress.

Provision 2. Nomenclature Committees. Permanent Nomenclature Committees
are established under the auspices of the International Association for Plant Taxonomy.
Members of these committees are elected by an International Botanical Congress.
The Committees have power to co-opt and to establish subcommittees; such officers
as may be desired are elected.

      1. General Comittee, composed of the secretaries of the other committees, the rapporteur-
général, the president and the secretary of the International Association for Plant Taxonomy,
and at least 5 members to be appointed by the Nomenclature Section. The rapporteur-général
is charged with the presentation of nomenclature proposals to the International Botanical
Congress.
       2. Committee for Spermatophyta.
       3. Committee for Pteridophyta.
       4. Committee for Bryophyta.
       5. Committee for Fungi and Lichens.
       6. Committee for Algae.
       7. Committee for Bacteria.
       8. Committee for Hybrids.
       9. Committee for Fossil Plants.
    10. Editorial Committee, charged with the preparation and publication of the Code in
conformity with the decisions adopted by the International Botanical Congress. Chairman: the
rapporteur-général of the previous Congress, who is charged with the general duties in
connection with the editing of the Code.

Provision 3. The Bureau of Nomenclature of the International Botanical Congress.

Its officers are: 1. The president of the Nomenclature Section, elected by the
organizing committee of the International Botanical Congress in question. 2. The
recorder, appointed by the same organizing committee. 3. The rapporteur-général,
elected by the previous Congress. 4. The vice-rapporteur, elected by the organizing
committee on the proposal of the rapporteur-général.

Provision 4. The voting on nomenclature proposals is of two kinds: 1. A pre-
liminary guiding mail vote and 2. A final and binding vote at the Nomenclature
Section of the International Botanical Congress.

Qualifications for voting:

A. Preliminary mail vote.

1. The members of the International Association for Plant Taxonomy.

2. The authors of proposals.

3. The members of the nomenclature committees.

Note. No accumulation or transfer of personal votes is permissible.

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B. Final vote at the sessions of the Nomenclature Section.

1. All officially enrolled members of the Section. No accumulation or transfer of personal
votes is permissible.

2. Official delegates or vice-delegates of the institutes appearing on a list drawn up by
the Bureau of Nomenclature of the International Botanical Congress and submitted to the
General Committee for final approval; such institutes are entitled to 1-7 votes, as specified
on the list. Transfer of institutional votes to specified vice-delegates is permissible, but no
single person will be allowed more than 15 votes, his personal vote included. Institutional
votes may be deposited at the Bureau of Nomenclature to be counted in a specified way for
specified proposals.

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Appendix I

Names of hybrids

Article H. 1

Hybrids are assigned to taxa of two principal ranks: interspecific hybrid and
intergeneric hybrid. These ranks are equivalent to species and genus respectively. The
nomenclature of these hybrids is governed by the general provisions of the Code,
except where modified by the special provisions of this Appendix.

Note. The term interspecific hybrid, whenever used in the Code, refers to a hybrid
between species of the same genus. The term intergeneric hybrid, whenever used in
the Code, refers to a hybrid between species of two or more genera.

Article H. 2

Hybrids or putative hybrids between two species of the same genus are designated
by a formula and, whenever it seems useful or necessary, by a name.

A formula consists of the names of the two parents connected by the multiplication
sign (× ) or of the name of the genus followed by the specific epithets of the two
parents connected by the same sign. The sequence of the names or epithets in a
formula is either alphabetical (as in this Code) or with the name or epithet of the
female parent first when this is known.

Example: Salix × capreola Kerner ex Andersson = Salix aurita L. × S. caprea L. or alter-
natively Salix aurita × caprea.

Recommendation H. 2A

The female (♀) and male (♂) signs may be added in formulas. Any other conventions
used in the writing of formulas should be explained by the authors.

Example: Digitalis lutea L. ♀ × D. purpurea L. ♂.

Article H. 3

A name of an interspecific hybrid is a binary combination consisting of the name
of the genus and a single epithet (‘collective’ epithet), the latter preceded by the
multiplication sign (× ). Such names are subject to the same rules as those for the
names of species (see Arts. 23, 40, & 50).

Example: Salix × capreola Kerner ex Andersson.

Where binary names of Latin form are used in the naming of hybrids, all des-
cendants (whether Fı or succeeding generations) of crosses between individuals of
the same parent species receive the same name (see Art. H. 10). An exception may
be made for names of amphidiploids and similar polyploids treated as species, which
may bear an epithet without the multiplication sign.

Example: Digitalis mertonensis Buxton & Darlington, a true-breeding tetraploid obtained
from D. grandiflora Mill. × D. purpurea L.

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Recommendation H. 3A

When polymorphic parental species are involved and if infraspecific taxa are recognized
in them, greater precision may be achieved by the use of formulae than by giving the hybrids
“specific” names.

Article H. 4

Designations consisting of the specific epithets of the parents combined in unaltered
form by a hyphen, or with the ending of only one epithet changed, or consisting of
the specific epithet of one parent combined with the generic name of the other (with
or without change of ending) are considered to be formulae and not true epithets.

Examples: The designation Potentilla atrosanguinea-formosa published by Maund is con-
sidered to be a formula meaning Potentilla atrosanguinea D. Don × P. formosa D. Don.

Verbascum nigro-lychnitis Schiede (Pl. Hybr. 40. 1825) is considered to be a formula,
Verbascum lychnitis L. × V. nigrum L.; the correct binary name for this hybrid is Verbascum
× schiedeanum Koch.

Article H. 5

If a statement of the parentage of a named interspecific hybrid appears to conflict
with the characters of the type of the name, the type takes precedence in determining
the application of the name.

Examples: Quercus × deamii Trelease was described as Q. alba L. × Q. muehlenbergii
Engelm. However, progeny grown from acorns from the type tree led Bartlett to conclude
that the parents were in fact Q. macrocarpa Michx. and Q. muehlenbergii. The hybrid Q.
alba × Q. muehlenbergii is left without a binary name, and the collective epithet × deamii
is applied to Q. macrocarpa × Q. muehlenbergii.

Article H. 6

Hybrids or putative hybrids between infraspecific taxa of the same species may be
designated by a formula and, whenever it seems useful or necessary, by a name of
the same taxonomic rank as the parents or, if these are of different rank, that of the
higher-ranking parent.

Example: Lilium davidii var. davimottiae (= L. davidii var. davidii × L. davidii var.
willmottiae).

Recommendation H. 6A

In the formula of a hybrid between infraspecific taxa, the order of the names or epithets
and the use of the signs ♀ and ♂ should follow the procedure set down in Art. H. 2 and
Rec. H. 2A. In general, greater precision will be achieved with less danger of confusion if
formulae rather than names are used for such hybrids.

Article H. 7

Intergeneric hybrids (i.e. hybrids between species of two or more genera) are
designated at the generic level by a formula and, whenever it seems useful, by a
“generic name”.

The formula consists of the names of the two or more parents connected by the
multiplication sign ×.

The “generic name” of a bigeneric hybrid (i.e. the name of a bigeneric hybrid
corresponding to a genus) is formed by combining the names of the two parent

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genera, i.e. the first part or the whole of one name and the last part or the whole
of the other, into a single word.

Examples: × Agropogon (= Agrostis × Polypogon); × Gymnacamptis (= Anacamptis
× Gymnadenia); × Gymnaglossum (=Coeloglossum × Gymnadenia); × Sericobonia (= Libonia
× Sericographis).

All hybrids between the same genera bear the same “generic name.”

The epithet of a bigeneric hybrid must not be placed under the name of either
of the parent genera.

Example: × Heucherella tiarelloides (= Heuchera × brizoides × Tiarella cordifolia), not
Heuchera × tiarelloides.

The “generic name” of an intergeneric hybrid derived from four or more genera
is formed from the name of a person eminent as a collector, grower, or student of
the group, to which is added the termination -ara; no such name may exceed eight
syllables.

Example: × Potinara (= Brassavola × Cattleya × Laelia × Sophronitis).

The “generic name” of a trigeneric hybrid is formed either like that of bigeneric
hybrids, by combining the names of the three parent genera into a single word not
exceeding eight syllables, or, like that of a hybrid derived from four or more genera,
from a personal name, to which is added the termination -ara.

Examples: × Sophrolaeliacattleya (= Cattleya × Laelia × Sophronitis). × Wilsonara (=
Cochlioda × Odontoglossum × Oncidium).

Note. The epithet of the name of a hybrid derived from two subdivisions of the
same genus is formed in the same way as the “generic name” of an intergeneric
hybrid.

Example: Iris subgen. × Regeliocyclus comprising the hybrids between species of Iris
belonging to subgenus Regelia and subgenus Oncocyclus.

Article H. 8

The “generic name” of an intergeneric hybrid is applicable only to plants which
are accepted taxonomically as derived from the genera named.

Example: If the genus Triticum L. is interpreted on taxonomic grounds as including
Triticum (s. str.) and Agropyron Gaertn., and the genus Hordeum L. as including Hordeum
(s. str.) and Elymus L., then hybrids between Agropyron and Elymus as well as between
Hordeum (s. str.) and Triticum (s. str.) are all to be placed within the hybrid group × Tritor-
deum Asch. & Graebn. (Syn. 2: 748. 1902). If, however, Agropyron and Elymus are separated
generically from Triticum (s. str.) and Hordeum (s. str.), hybrids between Agropyron and
Hordeum (s. str.) are placed within the hybrid group × Agrohordeum Camus (Bull. Mus.
Hist. Nat. Paris 33: 537. 1927), which has priority over × Hordeopyrum Simonet (Compt.
Rend. Acad. Paris 201: 1212. 1935). Hybrids between Agropyron and Elymus are placed in
× Agroelymus Camus (Bull. Mus. Hist. Nat. Paris 33: 538. 1927), which has priority over
× Elymopyrum Cugnac (Bull. Soc. Hist. Nat. Ardennes 33: 14. 1938, accompanied by a
statement of parentage and a description in French, but not Latin). Hybrids between Elymus
and Hordeum are placed in × Elymordeum Lepage (Natural. Canad. 84: 97. 1957); × Tritor-
deum is then restricted to hybrids between Hordeum (s. str.) and Triticum (s. str.). The
name × Hordelymus for hybrids between Elymus and Hordeum (s. str.) would be illegitimate
because of the earlier publication of Hordelymus (Jessen) Harz (Samenkunde 2: 1147. 1885)
based on Hordeum subgen. Hordelymus Jessen.

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Article H. 9

In order to be validly published, the name of a hybrid with the rank of genus or
subdivision of a genus, which is a condensed formula or equivalent to a condensed
formula (Art. H. 8), must be published with a statement of the names of the parent
genera or subdivisions of genera, but no description or diagnosis is necessary, whether
in Latin or in any other language.

Examples of validly published names: × Philageria Masters (Gard. Chrono 1872: 358),
published with a statement of parentage, Lapageria × Philesia; × Cupressocyparis Dallimore
(Hand-list Conif. Roy. Bot. Gard. Kew ed. 4. 37. 1938), published with a statement of
parentage, Chamaecyparis × Cupressus; Eryngium sect. × Alpestria Burdet & Miège (Can-
dollea 23: 116. 1968) published with a statement of its parentage, Eryngium sect. Alpina ×
sect. Campestria.

Article H. 10

When different hybrid forms or groups of hybrid forms derived from the same
parent species (including their infraspecific taxa) are treated as belonging to a
collective hybrid taxon of rank equivalent to species, they are classed under the
binary name applied to this taxon (see Art. H. 3) like infraspecific taxa under the
binary name of a species. These hybrid forms or groups of hybrid forms are termed
nothomorphs; when it is desirable, a nothomorph may be designated by an epithet
preceded by this binary name and the term “nothomorph” (nothomorpha, ab-
breviated as nm.).

In the hierarchy of ranks, nothomorph is equivalent to variety (see also Art. 50).

Note. Nothomorpha: — a term derived from the Greek νοθος and μορφη meaning
“hybrid form” and applied to any hybrid form, whether Fı, segregate or backcross.

Examples: Mentha × niliaca nm. lamarckii (a form of the pleomorphic hybrid Mentha
× niliaca = M. longifolia × M. rotundifolia); Ulmus × hollandica nm. hollandica and nm.
vegeta (forms of Ulmus × hollandica = U. carpinifolia × U. glabra).

An epithet published before 1 Jan. 1975 subordinate to the binary name of a
recognized hybrid, but at a rank other than that of nothomorph, is treated as pub-
lished at the rank of nothomorph, the name of the original author being cited,
followed by an indication of the original status (see Art. 50).

Example: Carduus × orthocephalus Wallr. nm. mulliganii Boivin (pro forma).

An epithet published on or after 1 Jan. 1975 subordinate to the binary name of a
recognized hybrid, but at any rank other than nothomorph, is not validly published.

Appendix II

Nomina familiarum conservanda see pp. 222-238

Appendix III

Nomina generica conservanda et rejicienda see pp. 239-393

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GUIDE FOR THE DETERMINATION OF TYPES

The following is intended as a guide to the determination or selection of the
nomenclatural types of previously published taxa. Where the application of a rule
is concerned, reference is made to the appropriate Article.

1. The choice made by the original author, if definitely expressed at the time
of the original publication of the name of the taxon, is final. If he included only
one element, that one must always be accepted as the holotype (Arts. 7, 9, 10). If a
new name is based on a previously published description of the taxon, the same
considerations apply to material cited by the earlier author.

2. A new name or epithet published as an avowed substitute (nomen novum)
for an older name or epithet is typified by the type of the older name (Art. 7,
par. 8).

3. A lectotype may be chosen only when an author failed to designate a holotype,
or when, for species or taxa of lower rank, the type has been lost or destroyed
(Art. 7, par. 3).

4. Designation of a lectotype should be undertaken only in the light of an
understanding of the group concerned. Mechanical systems, such as the automatic
selection of the first species or specimen cited or of a specimen collected by the
person after whom a species is named, should be avoided as unscientific and
productive of possible future confusion and further change. In choosing a lectotype,
all aspects of the protologue should be considered as a basic guide. (See Art. 8.)

a. A lectotype must be chosen from among elements that were definitely studied
by the author up to the time the name of the taxon was published and included in
the protologue.

b. Other things being equal, a specimen should be given preference over pre-
Linnaean or other cited descriptions or illustrations when lectotypes of species or
infraspecific taxa are designated, providing that the choice is in accordance with
Rec. 7B.

c. If a holotype was designated by the original author and has been lost or
destroyed, an isotype (Art. 7, par. 5), if such exists, must be chosen as the lectotype.
If no holotype was designated by the original author and if syntypes (Art. 7, par. 6)
exist, one of them must be chosen as the lectotype. If no holotype was designated by
the original author and if no syntypes are extant, the lectotype should be chosen from
among duplicates * of the syntypes (isosyntypes), if such exist. If neither an isotype,

———————

* The word duplicate is here given its usual meaning in herbarium curatorial practice. It is
part of a single gathering made by a collector at one time. However, the possibility of a
mixed gathering must always be considered by an author choosing a lectotype and cor-
responding caution used.

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a syntype, nor an isosyntype is extant, a paratype *, if such exists, may be chosen as
lectotype. If none of the specimens cited in the protologue nor any duplicates of them
are extant, a neotype (Art. 7, par.7) may be designated.

d. In choosing a lectotype, any indication of intent by the author of a name
should be given preference unless such indication is contrary to the protologue.
Such indications are manuscript notes, annotations on herbarium sheets, recognizable
figures, and epithets such as typicus, genuinus, vulgaris, communis, etc.

e. In cases when two or more elements were included in or cited with the original
description, the reviewer should be guided by Rec. 7B in the selection of a lectotype.
However, if another author has already segregated one or more elements as other
taxa, the residue or part of it should be designated as the lectotype provided that this
element is not discordant with the original description or diagnosis. If it can be
shown that the element or elements which remain are discordant, then one of the
previously segregated elements is to be selected as the lectotype (see Rec. 7B).

f. The first choice of a lectotype must be followed by subsequent workers (Art. 8)
unless the original material is rediscovered, or unless it can be shown that the choice
was based upon a misinterpretation of the protologue, or if the choice was made
arbitrarily (e.g., by a mechanical system) and without understanding of the group
concerned (see 4, above).

5. In selecting a neotype even more care and critical knowledge are essential, as
the reviewer usually has no guide except his own judgment as to what best fits the
protologue. If his selection proves to be faulty it will inevitably result in further
change. A neotype may be designated only when all the originally cited material
and its duplicates are believed lost or destroyed (Art. 7, par. 7).

The first choice of a neotype must be followed by subsequent workers unless the
original material is rediscovered, or unless the choice neglected an available lecto-
type, or if it can be shown that the choice was based on a misinterpretation of the
original protologue. A lectotype always takes precedence over a neotype (Art. 7,
par. 3).

6. For the name of a fossil species, the lectotype, when one is needed, should, if
possible, be a specimen illustrated at the time of the first valid publication.

———————

* A paratype is a specimen cited in the protologue other than the holotype, isotype(s), or
syntypes. In most cases where no holotype was designated there will also be no paratypes,
since all the cited specimens will be syntypes. However, in cases where an author cited two
or more specimens as types (Art. 7, par. 4), the remaining cited specimens are paratypes and
not syntypes.

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GUIDE TO THE CITATION OF BOTANICAL NOMENCLATURE

A reference to literature in a botanical publication should consist of the following
items, in the order in which they are treated below:

1. Name of author(s). In a citation appended to the name of a taxon, the name
of the author should be abbreviated as recommended in Rec. 46A. In other citations
(as in bibliographies), the name of the author should be given in full; the last name
first, followed by first name(s). The use of the full name (rather than initials)
tends to avoid errors.

If several authors are cited, the name of the last should be preceded by the
word et or by the sign “&” (see Rec. 46B).

After the name of a taxon, an unabbreviated author’s name should be separated
from what follows by a comma; an abbreviated name needs no punctuation other
than the period (full stop) indicating abbreviation.

2. Title. After the name of a taxon, the title of a book is commonly abbreviated,
and the title of an article in a serial is commonly omitted. Elsewhere (as in biblio-
graphies), titles should be cited exactly as they appear on the title-page of the book
or at the head of the article.

In a citation appended to the name of a taxon, no punctuation should separate
the title from what follows other than a period (full stop) indicating abbreviation.

Examples of taxonomic citation of authors and titles: P. Br. Hist. Jam. — Hook. f. Fl.
Brit. Ind. — G. F. Hoffm. Gen. Umbell. — G. Don, Gen. Hist. — H.B.K. Nov. Gen. Sp. —
L. Sp. Pl. — Michx. Fl. Bor.-Am. — DC. Prodr. — T. et G. Fl. N. Am. The last five authors’
names are not abbreviated strictly in accordance with Rec. 46A but with common usage.

Examples of names written in full: Mueller, Ferdinand Jacob Heinrich von. — Müller,
Johann Friedrich Theodor (“Fritz Müller”). — Mueller, Ferdinand Ferdinandowitsch. —
Müller, Franz August. — Müller, Franz.

3. Name of serial. Principal words should be abbreviated * to the first syllable,
with such additional letters or syllables as may be necessary to avoid confusion;
articles, prepositions, and other particles (der, the, of, de, et, and so forth) should
be omitted except when that omission might create confusion. The order of words
should be that which appears on the title-page. Unnecessary words, subtitles, and
the like should be omitted.

To avoid confusion among publications having the same name or veyy similar
names, the place of publication or other distinguishing data should be added in
brackets.

No punctuation other than a period (full stop) indicating abbreviation should
separate the name of the serial from what follows.

———————

* Titles consisting of a single word, and personal names, are customarily not abbreviated;
but many exceptions are sanctioned by usage.

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Examples of citation of names of serials: Ann. Sci. Nat.; not Ann. des Sci. Nat. — Am.
Journ. Bot.; not Amer. Jour. Bot. — Bot. Jahrb. (Botanische Jahrbücher für Systematik,
Pflanzengeschichte und Pflanzengeographie); not Engl. Bot. Jahrb. (Engler was the editor,
not the author of the series). — Mem. Soc. Cub. Hist. Nat. (Memorias de la Sociedad
Cubana de Historia Natural “Felipe Poey”). — Acta Soc. Faun. Fl. Fenn. (Acta Societatis
pro Fauna et Flora Fennica). — Bull. Jard. Bot. État [Bruxelles] (Bulletin du Jardin
Botanique de l’État). — Flora [Quito] (to distinguish it from the well-known “Flora”
published in Jena). — Hedwigia; not Hedwig. — Gartenflora; not Gartenfl. — Missouri Bot.
Gard. Bull.; not Bull. Mo. Bot. Gard. (see title-page).

4. Edition and series. If a book has appeared in more than one edition, those
subsequent to the first should be designated by “ed. 2”, “ed. 3”, and so forth.

If a serial has appeared in more than one series in which the numbers of volumes
are repeated, those subsequent to the first should be designated by a roman capital
numeral, or by “ser. 2”, “ser. 3”, and so forth.

Examples of editions and series: G. F. Hoffm. Gen. Umbell. ed. 2. — Compt. Rend.
Acad. URSS. II. (Comptes Rendus de l’Académie des Sciences de l’URSS. Nouvelle Série).
— Ann. Sci. Nat. IV. — Mem. Am. Acad. II. (or ser. 2.) (Memoirs of the American Academy
of Arts and Sciences. New Series); not Mem. Am. Acad. N.S.

5. Volume. The volume should be shown by an arabic numeral; for greater
clarity this should be printed in boldface type. When volumes are not numbered,
the years on the title-pages may be used as volume-numbers.

The volume-number should always be separated from the numbers of pages and
illustrations by a colon.

6. Part or issue. If a volume consists of separately paged parts, the number of
the part should be inserted immediately after the volume-number (and before the
colon), either in parentheses or as a superscript. For volumes which are continuously
paged, the designation of parts serves no useful purpose and leads to typographical
errors.

7. Pages. Pages are shown by arabic numerals, except those otherwise designated
in the original. If several pages are cited, the numbers are separated by commas; or
if more than two consecutive pages are cited, the first and last are given, separated
by a dash.

8. Illustrations. Figures and plates, when it is desirable to refer to them, should
be indicated by arabic numerals preceded by f. and pl. or t. (tabula) respectively;
for greater clarity these should be printed in italic type.

9. Dates. The year of publication should end the citation; or, in lists of works to
which reference is made by author and date, it may be inserted between the author’s
name and the title of his work. If it is desirable to cite the exact date, day, month,
and year should be given in that order. The date (in either position) may be
enclosed in parentheses.

Note. With the exceptions above noted, each item of the citation should be
separated from the following item by a period (full stop).

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Examples of citations appended to names of taxa: Anacampseros Sims, Bot. Mag. 33:
pl. 1367. 1811. — Tittmannia Brongn. Ann. Sci. Nat. 8: 385. 1826. — Monochaetum Naud.
Ann. Sci. Nat. III. 4: 48. pl. 2. 1845. — Cudrania Tréc. Ann. Sci. Nat. ser. 3. 8: 122. f. 76-85
1847. — Symphyoglossum Turcz. Bull. Soc. Nat. Mosc. 21¹: 255. 1848. — Hedysarum gremiale
Rollins, Rhodora 42: 230 (1940). — Hydrocotyle nixioides Math. & Const. Bull. Torrey Club
78: 303. 24 Jul. 1951. — Ferula tolueensis H.B.K. Nov. Gen. Sp. 5: 12. 1821. — Critamus
dauricus G. F. Hoffm. Gen. Umbell. ed. 2. 184. 1816. — Geranium tracyi Sandw. Kew Bull.
1941: 219. 9 Mar. 1942. — Sanicula tuberosa Torr. Pacif. Railr. Rep. 4(1): 91. 1857.

Examples of bibliographic citations: Norton, John Bitting Smith. Notes on some plants,
chiefly from the southem United States. Missouri Bot. Gard. Rep. 9: 151-157. pl. 46-50. 1898.

Reichenbach, Heinrich Gottlieb Ludwig. Handbuch des natürlichen Pflanzensystems. i-x,
1-346. 1837.

Don, George. A general history of the dichlamydeous plants. 1: 1-818 (1831). 2: 1-875
(1832). 3: 1-867 (1834). 4: 1-908 (1838).

Schmidt, Friedrich. Reisen im Amur-Lande und auf der lnsel Sachalin. Botanischer Theil.
Mém. Acad. St.-Pétersb. VII. 12²: 1-277. pl. 1-8. June 1868.

Glover, George Henry & Robbins, Wilfred WilIiam. 1915. Colorado plants injurious to
livestock. Bull. Colorado Exp. Sta. 211: 3-74. f. 1-92.

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BIBLIOGRAPHIA

LOIS / DE LA / NOMENCLATURE BOTANIQUE / ADOPTÉES PAR / LE
CONGRÈS INTERNATIONAL DE BOTANIQUE / TENU A PARIS EN AOUT 1867
/ SUIVIES D’UNE / DEUXIÈME ÉDITION / DE L’INTRODUCTION HISTO-
RIQUE ET DU COMMENTAIRE / QUI ACCOMPAGNAIENT LA RÉDACTION
PRÉPARATOIRE PRÉSENTÉE AU CONGRÈS / PAR / M. ALPH. DE CANDOLLE
/ Éditeur et en partie auteur du / Prodromus systematis naturalis vegetabilum. /
— / GENÈVE ET BALE / H. GEORG, LIBRAIRE-ÉDITEUR / PARIS / J.-B.
BAILLIÈRE ET FILS / 1867 /

In 8°; p. [1]-64; ‘Lois’: p. 13-32, ‘Commentaire’: p. 33-64. Sometimes referred to as ‘Paris
Code’ or ‘Paris Rules’.

RÈGLES INTERNATIONALES / DE LA / NOMENCLATURE BOTANIQUE /
ADOPTÉES PAR LE / CONGRÈS INTERNATIONAL DE BOTANIQUE DE
VIENNE 1905 / ET PUBLIÉES AU NOM DE LA COMMISSION DE RÉDACTION
DU CONGRÈS / PAR / JOHN BRIQUET / RAPPORTEUR GÉNÉRAL. / INTER-
NATIONAL RULES OF / BOTANICAL NOMENCLATURE / ADOPTED BY THE
INTERNATIONAL BOTANICAL CONGRESS OF VIENNA 1905. / — / INTER-
NATIONALE REGELN DER / BOTANISCHEN NOMENCLATUR / ANGENOMMEN
VOM INTERNATIONALEN BOTANISCHEN KONGRESS ZU WIEN 1905. / — /
VERLAG VON GUSTAV FISCHER IN JENA. / 1906. /

In 8° max.; p. [1]-99; Commission de Rédaction: J. Briquet, Ch. Flahault, H. Harms,
A. B. Rendle. Title on p. 17: ‘Règles internationales pour la Nomenclature botanique prin-
cipalement des plantes vasculaires’. Sometimes referred to as ‘Vienna Code’ or ‘First edition
of the Rules’. Also published in ‘Verhandlungen des internationalen botanischen Kongresses
in Wien 1905’, Jena 1906, pp. 165-261.

RÈGLES INTERNATIONALES / DE LA / NOMENCLATURE BOTANIQUE
/ ADOPTÉES PAR LE / CONGRÈS INTERNATIONAL DE BOTANIQUE DE
VIENNE 1905 / DEUXIÈME ÉDITION MISE AU POINT D’APRÈS LES /
DÉCISIONS DU CONGRÈS INTERNATIONAL DE / BOTANIQUE DE BRUXEL-
LES 1910 / PUBLIÉE AU NOM DE LA COMMISSION DE RÉDACTION DU
CONGRÈS / PAR / JOHN BRIQUET / RAPPORTEUR GÉNÉRAL / — / INTER-
NATIONAL RULES / OF BOTANICAL NOMENCLATURE / ADOPTED BY THE
INTERNATIONAL BOTANICAL CONGRESSES / OF VIENNA 1905 AND
BRUSSELS 1910 / — / INTERNATIONALE REGELN / DER BOTANISCHEN
NOMENCLATUR / ANGENOMMEN VON DEN INTERNATIONALEN BOTA-
NISCHEN KONGRESSEN / ZU WIEN 1905 UND BRÜSSEL 1910 / JENA /
VERLAG VON GUSTAV FISCHER / 1912 /

In 8° max.; p. [I]-VIII, [1]-110; Commission de Rédaction: J. Briquet, H. Harms, L.
Mangin, A. B. Rendle. Title on p. 12 (cf. p. 17, Vienna Code): ‘II. Règles internationales
de la Nomenclature botanique’. Sometimes referred to as ‘Brussels Code’, ‘Brussels Rules’,
‘Second edition of the Rules’.

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INTERNATIONAL RULES / OF / BOTANICAL NOMENCLATURE / ADOPTED
BY THE INTERNATIONAL BOTANICAL CONGRESSES / OF VIENNA, 1905,
AND BRUSSELS, 1910 / REVISED BY THE INTERNATIONAL BOTANICAL
CONGRESS / OF CAMBRIDGE, 1930 / COMPILED BY THE EDITORIAL COM-
MITTEE FOR NOMENCLATURE FROM THE REPORT OF / THE SUBSECTION
OF NOMENCLATURE PREPARED BY / JOHN BRIQUET (†) / — / RÈGLES
INTERNATIONALES / DE LA NOMENCLATURE BOTANIQUE / ADOPTÉES
PAR LES CONGRÈS INTERNATIONAUX DE BOTANIQUE DE VIENNE, 1905,
/ BRUXELLES, 1910, ET CAMBRIDGE, 1930 / — / INTERNATIONALE REGELN
/ DER BOTANISCHEN NOMENCLATUR / ANGENOMMEN VON DEN INTER-
NATIONALEN BOTANISCHEN KONGRESSEN ZU WIEN 1905, / BRÜSSEL 1910
UND CAMBRIDGE 1930 / DRITTE AUSGABE / — / VERLAG VON GUSTAV
FISCHER IN JENA / 1935 /

In 8° max.; p. [I]-[XII], [1]-[152]; General editor: H. Harms; English text (primary)
prepared by A. B. Rendle, in collaboration with J. Ramsbottom, T. A. Sprague and A. J.
Wilmott; French text prepared by B. P. G. Hochreutiner; German text prepared by H. Harms.
An unofficial abridged edition of the English text was issued by A. B. Rendle as a supple-
ment to ‘The Journal of Botany’, June 1934, entitled: ‘International Rules of Botanical
Nomenclature adopted by the Fifth International Botanical Congress, Cambridge, 1930’. The
abridgement consisted merely in the omission of most of the examples and of the Appendices.
Mostly referred to as ‘Cambridge Rules' or ‘Third edition of the Rules’.

International Rules of / Botanical Nomenclature / Formulated by the International
Botanical Congresses of Vienna, 1905, / Brussels, 1910, and Cambridge 1930 /
Adopted and revised by the International Botanical Congress of Amsterdam, 1935
/ Compiled from various sources by / W. H. Camp, H. W. Rickett and C. A.
Weatherby / UNOFFICIAL SPECIAL EDITION / Issued as a service to members
of the / American Society of Plant Taxonomists / Published by / THE NEW YORK
BOTANICAL GARDEN / in co-operation with / THE AMERICAN SOCIETY OF
PLANT TAXONOMISTS / THE SCIENCE PRESS PRINTING COMPANY /
LANCASTER, PENNSYLVANIA /
Top line: / Vol. 6, No. 1, pp. 1—120 BRITTONIA APRIL 9, 1947 /

    In 8°; p. [1]-120; Brittonia 6(1): 1-120. 1947.
    Second printing, 1948, reproduced by offset and published by the Chronica Botanica Co.
Waltham, Mass., U.S.A. for the New York Botanical Garden, and the American Society of
Plant Taxonomists.
    Mostly referred to as ‘Brittonia edition of the Rules’.

INTERNATIONAL RULES / of / BOTANICAL NOMENCLATURE / SUPPLE-
MENT / embodying the alterations made at the / Sixth International Botanical
Congress, Amsterdam, 1935 / compiled by / T. A. SPRAGUE, D. Sc. / late Deputy
Keeper of the Herbarium, Royal Botanic Gardens, Kew / Rapporteur Général for
Nomenclature, Sixth International Botanical Congress / — / (65) /

In 8°: In: Chronica Botanica, Volume 12, Number 1/2, pp. (65)-[88]. 1950.

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INTERNATIONAL CODE / OF / BOTANICAL NOMENCLATURE / ADOPTED
BY / THE SEVENTH INTERNATIONAL BOTANICAL / CONGRESS, STOCK-
HOLM, JULY 1950 PREPARED BY / J. LANJOUW, Chief Editor / CH. BAEHNI,
E. D. MERRILL, H. W. RICKETT, W. ROBYNS, / T. A. SPRAGUE, Members of
the Editorial Committee / F. A. STAFLEU, Secretary of the Committee / AVEC
UNE TRADUCTION FRANÇAISE / PAR / CH. BAEHNI / — / 1952 / UTRECHT
— NETHERLANDS / Published with financial support of I.U.B.S. by the / Inter-
national Bureau for Plant Taxonomy and Nomenclature of the / International
Association for Plant Taxonomy / The Chronica Botanica Co. : Waltham, Mass.
U.S.A.

In 8°; p.p. [l]-228; Regnum Vegetabile, A Series of Handbooks for the use of Plant
Taxonomists and Plant Geographers, Volume 3. Issued September 1952. Mostly referred to
as ‘Stockholm Code’.

INTERNATIONAL CODE / OF / BOTANICAL NOMENCLATURE / ADOPTED
BY / THE EIGHTH INTERNATIONAL BOTANICAL / CONGRESS, PARIS, JULY
1954 / PREPARED AND EDITED BY / J. LANJOUW, Chairman, / CH. BAEHNI,
W. ROBYNS, R. C. ROLLINS, R. ROSS, / J. ROUSSEAU, G. M. SCHULZE, A. C.
SMITH, R. DE VILMORIN, Members, / F. A. STAFLEU, Secretary of the Editorial
Committee / [I.A.P.T. emblem] / 1956 / UTRECHT — NETHERLANDS / Pub-
lished with financial support of I.U.B.S.—U.N.E.S.C.O. by the / International Bureau
for Plant Taxonomy and Nomenclature / of the International Association for Plant
Taxonomy /

In 8°; pp. [l]-338; Regnum Vegetabile, A Series of Handbooks for the use of Plant
Taxonomists and Plant Geographers, Volume 8. Issued December 1956. With similar French,
German and Spanish title pages on pp. [2], [4] and [5]. Mostly referred to as ‘Paris Code’.

INTERNATIONAL CODE / OF / BOTANICAL NOMENCLATURE / ADOPTED
BY / THE NINTH INTERNATIONAL BOTANICAL CONGRESS / MONTREAL,
AUGUST 1959 / PREPARED AND EDITED BY / J. LANJOUW, Chairman, / CH.
BAEHNI, W. ROBYNS, R. ROSS, J. ROUSSEAU, J. M. SCHOPF, G. M. SCHULZE,
/ A. C. SMITH, R. DE VILMORIN, Members, / F. A. STAFLEU, Secretary of the
Editorial Committee / [I.A.P.T. emblem] / 1961 / UTRECHT — NETHERLANDS
/ Published with financial support of I.U.B.S.-U.N.E.S.C.O. / by the International
Bureau for Plant Taxonomy and Nomenclature / of the International Association
for Plant Taxonomy /

In 8°; pp. [1]-372; Regnum Vegetabile, A series of publications for the use of plant
taxonomists and plant geographers, volume 23. Issued December 1961. With similar French
and German title pages on pp. [2] and [4]. Mostly referred to as ‘Montreal Code’.

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INTERNATIONAL CODE / OF BOTANICAL NOMENCLATURE / ADOPTED
BY / THE TENTH INTERNATIONAL BOTANICAL CONGRESS / EDINBURGH,
AUGUST 1964 / PREPARED AND EDITED BY / J. LANJOUW, Chairman, / S. H.
MAMAY, R. McVAUGH, W. ROBYNS, R. C. ROLLINS, R. ROSS, J. ROUSSEAU,
/ G. M. SCHULZE, R. DE VILMORIN, Members, / F. A. STAFLEU, Secretary of
the Editorial Committee / [I.A.P.T. Emblem] / 1966 / UTRECHT — NETHERLANDS
/ Published with financial assistance of I.U.B.S. - I.C.S.U. - U.N.E.S.C.O. / by the
International Bureau for Plant Taxonomy and Nomenclature / of the International
Association for Plant Taxonomy /

In 8°; pp. [1]-402; Regnum Vegetabile, A series of publications for the use of plant taxon-
omists, volume 46. Issued December 1966. With similar French and German title pages on
pp. [4] and [5]. Mostly referred to as ‘Edinburgh Code.’

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KEY TO THE NUMBERING OF THE ARTICLES AND RECOMMENDATIONS

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[ Not present in this edition ]

[ sic ]

[ supposed to be superscript ]