THE CANADIAN ENTOMOLOGIST. 193 



I have bred from the egg four of our larger species of Argynnis, viz., 

 diana, cybele, aphrodite and idalia, and have had the egg and chrysalis of 

 atlantis, and have drawings of the several stages of each species ; 

 and now having bred myrina, I can say that so far as I have 

 seen of the preparatory stages of all these species, they are congeneric 

 The simple difference that is found among them is not in the shape of the 

 eggs, or the forms and habits of the caterpillars, or the forms of the 

 chrysalids, but merely in the behavior of myrina as regards the second 

 brood, each of the others being, so far as is yet known, single brooded.* 

 And neither in the preparatory stages nor in the butterflies themselves 

 do I see any reason for separating myrina and the smaller species 

 from the genus Argynnis, or making more of them than a group. A 

 group is as expressive as a genus, and a genus with its groups should pre- 

 sent at one view an entire class with all its families, inter-related, though 

 in differing degrees, as having had a common ancestor, and any system of 

 arrangement which elevates what are properly groups into independent 

 genera, destroying the unity of the class, strikes me as unnatural, and 

 therefore unphilosophical. 



But in passing we may as well look into the facts about this genus 

 Brenthis — Brenthis Hiibner (Scud. Syn. List, 1875) and learn something 

 about the manufacture of modern genera. 



The species myrina is closely like cuphrosyne of Europe, and con- 

 generic with it, no matter how Argynnis be split up. Hiibner, in his 

 Verzeichniss, amused himself with assorting the known butterflies into 

 batches or parcels, as a child would sort his alleys and taws, by color, 

 stripes and shape, putting blues into one lot, browns into another, one- 

 striped into a third, two-striped into a fourth, regardless of characters 

 which would be generic, that is. which would indicate blood relationship 

 or a common descent. It is a very rare thing to find one of his batches 

 — which he called a coitus, meaning a batch or assemblage, and which is 

 in no sense a genus, for the element of common descent does not enter 

 into this whimsical system — co-extensive with a genus. It is by the 

 merest chance if it is so. Nor does the coitus correspond with a natural 



* Though there are some reasons for suspecting that in West Virginia the other 

 species must he double brooded also. That, however, is not determined, and 1 do 

 not assume it. But this difference in the same genus as regards the number of 

 broods, supposing it exists in Argynnis, is paralleled by the Apaturas cettis and 

 clyton, the former being here double, the latter single brooded. 



