162 HICKORY. LEAVES HICEOEY TUSSOCK-MOTH. 



half gi-own they scatter themselves and thenceforth live apart and 

 solitary. The state of the atmosphere influences them somewhat 

 as to the time of spinning their cocoons. Ten worms which I 

 reared in a cage together from their infancy, after a period of 

 severe drouth, on the occurrence of a rainy day the second of 

 Septembei, spun their cocoons simultaneously, all save one, which 

 performed this labor ten days earlier. When ready to form its 

 cocoon the caterpillar crawls into some secure cavity, in the 

 crevices of a wall or beneath a stone, to which the cocoon is very 

 slightly attached. From this the winged moth is given out the 

 following spring, though when reared in a dry room I have known 

 individuals to come forth in their winged state the latter part of 

 October and in November. The^e moths pertain to the family 

 Arctiid^ or the Tiger-moths. They cannot be referred to any 

 of the genera defined by the European naturalists, and Dr. Harris 

 (New England Insects, p. 279) has therefore constructed for them 

 a genus which he names Lophocampa, a word meaning crested 

 caterpillar. He indicates four species pertaining to this genus, 

 and the caterpillars of two additional species are known to me. 



The Cocoons of the hickory tuasock-moth are of a regular oval form, nearly an 

 inch long and over a half inch broad, of an ash gray color, composed exteriorly of the 

 short stiff" hairs of the caterpillars, woven loosely together and with their points 

 standing in all directions, so that it is impossible to touch one of these cocoons with- 

 o'ut having the skin filled with these hairs, resembling cowhage and producing 

 the same irritation of the skin which that substance causes. The pencils of 

 long black hairs of the caterpillar are separated and drawn in among the others 

 so skilfully that the eye is seldom able to discern their color. The whole are 

 Md together by » thin clothlike fabric formed of white silken threads matted 

 closely together which lines the cocoon upon its inner side. Its 

 texture is so slight that when the moth is ready to leave the cocoon, 

 by merely crowding its head forward it ruptures it at one end and 

 forms a round orifice through which it makes its exit, elongating 

 the cocoon slightly hereby, at this end, as represented in the ac- 

 companying figure. 



The Chktsalis or Pupa lies in the cocoon with the black head and other relics of 

 the larva at its pointed end. It is 0.70 long by 0.30 in diameter, of a pale chestnut 

 color, its sutures marked by slender black impressed lines and the breathing pores 

 forming a row of, seven oval black dots along each side. Its surface is smooth, with- 

 out those rows of little spines which we see in the pupa of the peach borer and seve- 

 ral other moths, and the empty shell remains within the cocoon after the moth ig 

 disclosed. The figure presents a dorsal view of the sutures, breath- 

 ing pores, &c.,but is unduly contracted on the anterior half, the 

 width here being the same as across the middle. 



