276 BUTTERFLIES 



the same oak barrens as the other, the blueberry blossoms 

 being freely visited for nectar by both species. 



Persius's Dusky-wing 



Thanaos persius 



This is a rather small, dark brown Skipper, with a few 

 white spots toward the apex of the front wing, but other- 

 wise not marked except for a very pale transverse band 

 which is almost obsolete. The butterfly is found from 

 ocean to ocean along the northern tier of states. It also 

 occurs in the Eastern states as far south as Florida as well 

 as in the states along the Pacific Coast. 



The food plants of the caterpillars differ from most of 

 those of the other Skippers. The butterflies lay their 

 yellowish green eggs, one in a place, upon the leaves of 

 willows and poplars. These soon hatch into little cater- 

 pillars each of which cuts out a small flap along the margin 

 of the leaf and folds it over, fastening it in place with silken 

 threads. It thus forms a protecting nest within which it 

 remains during the day, going forth at night to a neighbor- 

 ing part of the same leaf or to another leaf, and feeding 

 upon the green surface tissues. In this first caterpillar 

 stage it does not eat the veins to any extent. As it be- 

 comes larger it constructs a larger nest and feeds more 

 freely upon the leaf tissues. When about half grown it has 

 the curious habit of biting out small holes here and there in 

 the blade so that the leaf takes on a very unusual appear- 

 ance. The presence of these holes is generally the easiest 

 way to find the caterpillars, for when the holes are seen, a 



