THE GOSSAMER-WINGED BUTTERFLIES 



A. Radius of the front wings four-branched. 



B. Body comparatively stout ; colors of the upper surface of 

 the wings orange red with a coppery luster, or brown with 

 a coppery tinge, in each case spotted with black, p. 236. 



The Coppers. 



BB. Body slenderer ; colors of the upper surface of wings 

 blue or bluish black, p. 244. The Blues. 



AA. Radius of the fore wings only three-branched, p. 217. 



The Hair-Streaks. 



The Hair-streaks 



The hair-streaks are distinguished from the other gossamer- 

 winged butterflies by the fact that radius of the fore wings 

 is only three-branched. They are usually dark brown, with 

 delicate striped markings on the lower surface of the wings, 

 which suggested to some person of vivid imagination the 

 common name given above ; but some species are brilliantly 

 marked with metallic blue or green. The hind wings are 

 also commonly furnished with delicate taillike prolongations. 

 The fore wings of the male often bear a small dull oval spot 

 near the middle of the costal part of the wing, the discal 

 stigma, which is filled with the peculiar scent-scales known as 

 androconia. The males are also distinguished by having a 

 tuft of hairlike scales, the beard, on the front; this is want- 

 ing or very thin in the females. About fifty species occur in 

 America north of Mexico ; our most common species, which 

 are described below, can be separated by the following table: 



A. Hind wings with a long, slender, taillike prolongation at 

 the end of vein Cu,, and sometimes with a similar one at the 

 end of vein Cu,. 



217 



