NOMENCLATURE OF FUNGI. 
IOI 
acteristics of a species, and the description which is drawn from 
such specimen is consequently and inevitably incomplete. But 
the name, nevertheless, applies to the whole species, to all its 
variations in aspect, to every member of the species, and to each 
individual in all stages of development, and in all its structural 
parts. The fact that the author of the name, in establishing it by 
a published description, did not mention all the characters to be 
derived from the various parts of the plant, or its various stages 
of growth, does not in the least invalidate the name, or restrict its 
application. The author may have been ignorant of some of the 
characters, or have misunderstood others, and yet the name is 
not invalidated or restricted. The name of a species is the name 
of the whole species. 
When a name is applied to a part of a species, that is, to the 
species in a certain stage of development, or when it assumes cer¬ 
tain appearances, or when it is applied to similar parts of several 
species, it stands for what is known as a form species. When 
the same method is pursued with genera, we have form-genera. 
Such species and genera compose the very large group of forms 
known as fungi imperfecti, and they are not uncommon among 
many families of fungi, and of other plants as well. Such names 
are necessary and useful until greater knowledge of the plants can 
be obtained, and their true relationship be established. 
If we turn now to the example with which we began, and under¬ 
take to decide from which of the names applied to the wheat 
rust, Aecidium ( Lycoperdon ) poculiforme, Uredo (Ly coper don) 
line cere and Puccinia graminis, the specific name should be taken in 
order to accord with modern usage, it will readily be seen that 
the selection will depend in the first place upon the conception 
held regarding the genus Puccinia. If it is correct usage to re¬ 
strict the specific name to that applied to the teleutosporic stage, 
because Persoon in founding the genus, and mycologists of more 
recent times as well, have drawn the characters chiefly from the 
teleutospores, then the name should be written Puccinia graminis. 
But if this is accepted, the genus Puccinia is not a true genus, but 
a form-genus, for it represents only one of the three stages of 
development. If it is a true genus, it embraces all stages of 
