marks, appropriate to their status as a designation rather than a name (i.e. not validly published), and are sometimes cited (though not in the Code) as “orth. var.” Confusingly similar names based on the same type are treated as orthographical variants (Art. 61.5). For example, Nelumbo Adans. 1763 and “Nelumbium” (Jussieu, 1789: 68) are spelling forms of a generic name based on Nymphaea nelumbo L., and are treated as orthographical variants. Even if Jussieu’s “Nelumbium” had been intended as a new name, it was confusingly similar to Nelumbo and was based on the same type; hence it is treated as an orthographical variant. In effect, Jussieu used Adanson's name, albeit with a correctable spelling mistake.
Occasionally the original publication may contain more than one orthographical variant. In such cases, Art. 61.3 rules on which one is to be retained: the one that conforms to the rules and best suits the recommendations of Art. 60. However, if the variants conform and suit equally well, a nomenclatural act decides which variant is to be retained, i.e. the first choice appearing in an effectively published text, in which an author explicitly adopts one of the variants and rejects the other(s).
GENDER
All generic names have a gender: masculine, feminine, or neuter. This is significant because adjectival epithets in the names of subdivisions of genera, species, and infraspecific taxa must agree in gender with the generic name (Art. 21.2, 23.5, and 24.2). If they do not, the names are validly published but the terminations of the epithets are to be corrected without change of the author citation or date of the name (Art. 32.2). Of course, it is quite possible for there to be no adjectival epithets among the names of the subordinate taxa of some small genera.
There are some general trends that are worth remembering. Names ending in -us (e.g. Agaricus, Astragalus) tend o be masculine, unless they are names of trees, in which case they tend to be feminine (Aesculus, Prunus, Quercus, Ulmus). Names ending in -a and -is are nearly always feminine (Rosa, Yucca; Cannabis, Orchis), unless they end in -ma, in which case they tend to be neurer (Aliema, Melasoma). Names ending in -um are always neuter (Allium, Lilium).
The rules on gender are in Art. 62 of the Code. The basic rule is Art. 62.1, which states that a generic name retains the gender assigned by nomenclatural tradition. The gender of nomenclatural tradition usually, but not always, coincides with the classical gender of the corresponding Greek or Latin word, if any, e.g. Quercus L. 1753 is feminine in nomenclatural tradition and the classical gender of the Latin word quercus (oak) is also feminine. If the classical usage of the name or the author’s original usage of the name is different, it does not override the nomenclatural tradition. If there is no nomenclatural tradition, the genetic name retains the gender assigned by its original author (also Art. 62.1).
A USER'S GUIDE TO THE INTERNATIONAL CODE OF NOMENCLATURE FOR ALGAE, FUNGI, AND PLANTS0