SOME PROBLEMS OF TAXONOMY 
299 
lem, which is intimately associated with the second of our hypo- 
thetical species. However, it might well be based on such a 
species as Euxoa tessellata Harris or E. messoria Harris. The 
entire diagram represents the hypothetical cross section, the 
species under consideration. Z, the inner circle enclosed by an 
unbroken line, may again be taken as the basic and nimotypical 
form, overlapped as represented by the dotted circle, by each of 
the variations v, w, x and y. These variations, whether races or 
forms, may also overlap each other as shown. Obviously, to a 
nan possessing series or specimens only from the sections b of 
these variations, they would seem abundantly distinct and de- 
serving of names. By supplementing this material with other 
specimens from the a zones he would at once perceive their inter- 
gradation and the necessity for great circumspection in their 
treatment. Such variations appear to be incipient forms, possi- 
bly incipient species, but at such an early stage in their evolu- 
tion that their right even to be named may be seriously ques- 
tioned. All belong to species z, and to any but a laboratory 
scientist or a student of heredity the simple binomial Ga would 
be much more useful that a long series of named, intergrading 
forms. The work done in late years on heredity in Drosophila 
is an excellent case in point.^^ What a galaxy of named Droso- 
phila forms we should have if the geneticists showed the same 
tendencies as some of our systematists ! Another unfortunate 
feature of such species is that they may produce a distinct form 
such as u. The probable treatment of such a form would be 
assignment to a rank equal to that of v, w, x and y, although it 
alone might deserve to be called a form or race. I venture the 
assertion that many species of our present classification, at 
least in the order Lepidoptera, will fit more satisfactorily as sub- 
divisions in such a classification as this than in their present 
arrangement. Mr. F. H. Benjamin has already done an excel- 
lent piece of work on this basis in the genus Lampra Hiibner 
( Rhynchagrotis Smith) 
Although, as is natural, the foregoing considerations have been 
illustrated by mention of insects whose study gave rise to them, 
an attempt has been made to formulate them in such a general 
way that each individual may adapt them to his own fund of 
Morgan et al., Mechanism of Mendelian Heredity, 1915, and other works. 
Benjamin, F. H., A Study of the Noctuid Moths of the Genera Lampra 
Hbn. and Cryptocala gen. nov., Bull. S. Cal. Acad. Sci. xx, part 3, 1921. 
