LEPIDOPTERA. 373 



discal patch, which usually appears to the naked eye like 

 a scorched, oblique streak near the center of each fore 

 wing (Fig. 454). This patch is a complicated organ, com- 

 posed of tubular scales that are outlets of scent-glands 

 and other scales of various shapes. The females can be 

 recognized by their resemblance in other respects to the 

 males. In some species the discal patch is wanting in the 

 males also. 



This subfamily is an exceedingly difficult one to study. 

 More than one hundred species have been described from 

 America north of Mexico ; and in many cases the differences 

 between allied species are not well marked. The following 

 two are named merely as examples, The first is easily 

 recognized. But it is not worth while for the beginning 

 student to attempt to distinguish other members of this 

 subfamily. 



The Least Skipper, Ancyloxipha numitor (An-cy-lox'i-pha 

 nu'mi-tor). This skipper is the smallest of our common 

 species, and is also remarkable for lacking the recurved 

 hook at the tip of the antennae. The wings are tawny, 

 broadly margined with dark brown. In some specimens 

 the fore wings are almost entirely brown. The larger in- 

 dividuals expand about one inch. The larva feeds upon 

 grass in damp places. 



The Black Dash, Limochores pontiac (Li-moch'o-res 

 pon'ti-ac). The male of this species is represented by 

 Figure 454. It is blackish brown, with considerable yellow 

 on the basal half of the fore wings. The discal patch is 

 velvety black. This species is distributed from Massachu- 

 setts to Nebraska. 



Superfamily PAPILIONINA (Pa-pil-i-o-ni'na). 



The Butterflies. 



The butterflies differ from moths in that they have 

 clubbed antennae., fly only in the daytime, and hold the 



