BUTTERFLIES OF MONTANA. 13 



Key for Determation of Butterflies. 



1. Antennae thread-like with a knob at the extremity. 2. 



2. With the radius of the fore-wings five-branched, Fig. 8, and with all 



the branches arising from the discal cell; club of antennae usually 

 terminated by a recurved hook. The Skippers. Hesperiina, page 142 



3. With some of the branches of the radius of the fore-wwings coalesced 



beyond the apex of the discal cell, Fig. 7; club of antennae not 

 terminated by a recurved hook. Butterflies. Papilionina, pagelS 

 SUPERFAMILY PAPILIONINA. 

 Key to Families. 



1. Cubitus of the fore-wings apparently four-branched, Fig. 7. 



Papilionidae. P. 13 

 Cubitus of the fore-wings apparently three-branched, Fig. 11. 2. 



2. With six well developed legs, although in some species the fore legs 



of the male are a little shorter, and the tarsi of these lack one or 

 both claws; radius of the fore wings, with rare exceptions, only 

 three or four-branched. To determine the number of branches of 

 radius, count the two cubital and the three medial branches first; 

 the branches left between veins V and II belong to the radius. 3. 

 With only four well developed legs, the fore legs being unused, much 

 shorter than the others, and folded on the breast like a tippet (ex- 

 cept in the female of Hypatus) . Radius of fore wings five-branched, 

 Fig. 11. Nymphalidae. P. 44 



3. Vein V of the fore-wings arising at or near the apex of the discal cell, 



Fig. 9, except in Feniseca tarquinius, in which the wings are dark 

 brown, with a large fulvous spot on each. Lycaenidae. P. 124r 

 The first branch of media of the fore wings united with the last 

 branch of the radius for a considerable distance beyond the apex 

 of the discal cell. Fig. 10. Ground color of the wings white, yellow 

 or orange. Pieridae. P. 26 



FAMILY PAPILONIDAE. 

 Key to the Subfamilies. 



Hind wings with a tail like prolongation; ground color of wings black; 

 radius of fore wings five-branched; the base of vein VIII of fore 

 wings preserved as a spur like branch of vein VII, Fig. 7. 



Papilioninae. P. 1& 



Hind wings without tail like prolongation; ground color of wings white; 

 radius of fore wings four-branched; vein VIII of fore wings want- 

 ing, Fig. 12. Parnassiinae. P. 13 



SUB-FAMILY PARNASSIINAE. 



The Parnassiinae differ from the Papilioninae in lacking the tail-like 

 prolongation of the hind wings and in that the ground color of the wings 



