RILEY — HACKBERRY BUTTERFLIES. 



both species occur, and I have often found their larvae feeding on 

 the same tree. Herse is, however, less common than Lycaon. 

 Boisduval gives Prunus as food-plant of the species, but it has 

 never been since recorded as occurring on trees of that genus, 

 and Mr. Samuel H. Scudder, of Plymouth, N. H., to whom I sent 

 young larvae, found that they refused plum-leaves, and died rather 

 than eat of them. 



\_Fig: 6.] 



Apatura Herse— ^, larva, half grown, dorsal view *\ h , imago J 1 underside — natural 

 size; i, J, k, I, m, the five different heads of larva; n, o, dorsal and lateral views of larval 

 joint; /, egg — enlarged; q, larva; as when hibernating — nat. size. 



The eggs of Herse (Figs. 5, a, and 6,/), unlike those of its con- 

 gener, are invariably deposited in dense batches of from 300 to 

 500, and two, or more often three, tiers deep. Otherwise they dif- 

 fer from those of Lycaon mainly in being a little broader on the 

 crown. When first laid they are pale yellowish-white, but, towards 

 hatching, the mass, if uninjured, acquires a deeper buff color. — 

 The larva, in the first stage, is easily distinguished by its copal- 

 yellow, instead of black, head ; and in the other stages by having 

 a dark medio-dorsal line, and a straight, instead of a wavy, supra- 

 stigmatal line. The head is also larger, more pubescent, broader 

 at top, and with the antlers larger, more spiny, and more hairy. 

 The spines vary somewhat in sharpness and size, but are often 

 very conspicuous in the third molt, when a worm at rest presents 

 a really singular appearance (Fig. 6,g). These larvae are more 

 or less gregarious up to the third molt, after which they scatter. 

 The habit, after they scatter, of hiding within leaves drawn around 

 them, is more determined than in Lycaon ; and the young of the 



