143 BIOGRAPHY OF HEMILEUCA MAI A. \\ 



ruinated, wliile its principal branches have the termination and arma- 

 ture of those elsewhere. 



At this age, the larva was observed to carry a thread with it in all 

 its movements over the leaf. 



On the morning of the 9th, the larvae had taken position for another 

 molting, and were of the length of .45 of an inch. 



Second molting. Two and a quarter days from the time above 

 noted, or at noon of the llth, the first of the colony molted for tho 

 second time, and the entire number before the close of the day.* 

 A half hour after the change, the head of the larva was of a rufous 

 color. The body, fuscous with obscure red stigrnatal spots, and 

 sprinkled with rufous granulations, of which there is a larger one 

 laterally on each segment below the subdorsal row of spines. Spines, 

 rufous, with fulvous branches ; those of the two superior rows tipped 

 with a bristle, often black and numerously branched ; the lateral spines 

 less branching, and tipped with longer fulvous bristles. The legs and 

 prolegs, rufous ; the former with the tarsus black. Three hours after 

 the molt the larvae had changed to a uniform reddish-brown color. 



During this stage of development, the larvae disclosed characters in 

 accordance with descriptions and representations of H. Maia, which 

 enabled me to refer them to that species. 



Third molting. June 20th.f Length of larva, one inch. Color, 

 fuscous. Spines of the two superior rows on segments 3-10 and the 

 mesial one on segment 11, red with their terminal third black, simple, 

 fasciculate, thickly radiating from a black, slightly elevated tubercle ; 

 the other spines are glossy black, sparsely branched, the branches 

 cylindrical, whitish near their tips, and having inserted in them a 

 delicate, acute black bristle. Stigmata linear, tawny colored. 



Sting of larva. Some experiments made with the larva subse- 

 quent to the molting above recorded, in examination of its stinging 

 powers, which were first noticed at this stage of its growth, indicate 

 its possession of this means of defense in a degree considerably exceed- 

 ing that of the closely allied species, Hyperchiria lo (Fabr.) 



A larva was dropped three or four times from a height of about ten 

 inches upon the back of the first joint of the thumb. The sensation 

 did not differ materially in kind from the sting of the nettle, but was 

 more acute. In a few minutes the surface became reddened, and in a 

 short time numerous slightly elevated whitish blotches made their 

 appearance, accompanied with a burning and itching. The following 



* Of their exuviae, a small number had the head case attached; of those which 

 were separated, nearly half had the collar, with its spines, united to the head-case. 



f About one-half of the cast skins were separated from their head-cases, and nearly 

 all of the cases had attached to them the collar, bearing its four spines. 



