INTERNATIONAL RULES’ FOR BOTANICAL NOMENCLATURE 9 
Article 29. Two subspecies of the same species cannot have 
the same name. A ta name can only be used once for a variety 
of a given species, when dealing with varieties which are 
classed — different subspecies The same holds for subvarieties 
and for 
letoclada and Rosa 8) Wtinosa var. letoclada ; Viola tricolor var, rta, 
in spite of the “ce alrea dy of a different species named Viola 
hirta. The following are incorrect : Erysimum hieraciifolium subsp. 
strictum var. acest dh EF, hieractifolium subsp. pannonicum 
var. longistliquum—a form of nomenclature which allows two varie- 
ties bearing the same name in thie i same species. 
RecomMenpation. 
VI. Botanists are recommended to use as little as possible 
the privilege granted in the second part of Article 29, in order to 
cigs: feta on and mistakes, and also to reduce to a minimum the 
necessary changes of name yes the subdivisions of species are 
ats to specific rank, or vice v 
Article 30. Forms and half. brands among cultivated Sora 
should receive fancy names, in common angua erent as 
possible from the Latin names of the species or varieties. When 
they can be traced back to a Species, a subspecies, or a: botani 
variety, this is indicated by a succession of names. 
Example: Pelargonium zonale Mrs. Pollock. 
§ 5. Names of Hybrids and Half-breeds eae 
Article 31. Hybrids between species of the same genus, or 
presumably so, are designated by a formula, and, @ucnever it seems 
usefal or necessary, by a name. 
The formula consis ts of the names or specific epithets of the 
and by the sign x "belées the name. 
Examples: x Salix capreola = Salix aurita x wig to Digitalis 
lutea 2 X purpurea J; Digitalis lutea 3 X purpurea 2. 
Article 32. Intergeneric hybrids (between species of different 
genera), or presumably such, are also —— by a formula, and, 
when it seems useful or necessary, by a 
The formula consists of the names of a two parents, in alpha- 
betical order 
The hybrid i is associated with the one of the two genera which 
precedes the other in alphabetical order. The name is preceded by 
n X; 
