Genus Parnassius 



Fig. 149. — Neuration of the 

 genus Parnassius. 



The wings are generally translucent on the margin, with a rounded 



apex. The upper radial is lacking. The subcostal is five-branched, 



the third, fourth, and fifth nervules being 



emitted from a common stalk which 



springs from the upper outer angle of the 



cell. The first subcostal nervule rises 



well before the end of the cell ; the second 



from the same point from which the stalk 



which bears the other three nervules 



springs. The cell of the hind wing is 



evenly rounded at its outer extremity. 



The inner margin of the hind wing is 



more or less excavated. 



Early Stages. — The egg is turban- 

 shaped, flattened, profusely covered 

 with small elevations, giving it a sha- 

 greened appearance. The caterpillars 

 have very small heads. They are flat- 

 tened, having a somewhat leech-like appearance; they are black 

 or dark brown in color, marked with numerous light spots. The 

 chrysalis is short, rounded at the head, and pupation takes place 

 on the surface of the ground, among leaves and litter, a few loose 

 threads of silk being spun about the spot in which transformation 

 occurs. 



The butterflies of this genus are classified with the Papilioni- 

 nce, because of the fact that the internal vein of the hind wings is 

 always wanting, a characteristic of all papilionine genera. 



(1) Parnassius clodius, Menetries, Plate XXXIX, Figs. 7, 9, 

 $ ; Figs. 8, 10, S (Clodius). 



Butterfly. — The species may be distinguished from the follow- 

 ing by the uniformly larger size and the more translucent outer 

 margins of the fore wings in the male. Expanse, $, 2.50-2.75 

 inches; $, 2.50-3.00 inches. 



Early Stages. — These await study. The egg and young larva 

 were described by W. H. Edwards in the "Canadian Entomolo- 

 gist," vol. xi, p. 142, but we have no account of the later stages. 

 The caterpillar feeds on Sedum and Saxifraga. 



Clodius is found upon the mountains of California in spring 

 and early summer. It is, like all its congeners, an alpine or boreal 

 species. 



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