1512 Till': HU'ITERFLTKS OF XEW ENGLAND. 



tlie same larva here from English filbert [a species of Corylus of the 

 allied tamily Cupuliferae] hut tlie imago failed to appear." This is the 

 larva figured on our plate, but that it certainly ijelongs to the present 

 species (considering the close resemblance between the caterpillars of some 

 of the species and our lack of familiarity witii tliem all) requires verifica- 

 tion. Fitch i-aised a sjiccinicn of Tiianaos from witcii-liazcl, Ilaniamaelis, 

 a widely difiercnt plant, and tiie dcsci-iption of tiie buttertiy he has left in 

 his notes renders it almost certain tiiat it was this species. Finally, when 

 this seemed to be the only species fiying at Xepigon, Mr. Fletcher and I 

 found eggs of a Thanaos (presumably, therefore, this species) on Salix 

 cordata. 



Habits of the caterpillar. Icelus makes a nest in the usual manner 

 of the species of Thanaos ; but the threads are usually very long, so as to 

 leave abundance of space for air or indeed the entrance of nearly any 

 enemy ; when the time for a change of skin comes these are all tightened 

 and the edge of the overhanging bit of leaf brought into close contact with 

 the surface opposed to it, leaving only at one end just room enough to 

 crawl out. When the change is effected, and a new home is desired, these 

 threads are completely cut by the caterpillar before deserting the nest, 

 which then remains half opened. During rest the caterpillar remains up- 

 side down on the overhanging flap. It eats only the leaf on which its nest 

 is made, but feeds at some distance from the nest and apparently only by 

 niglit. A caterpillar that had just made its third moult was placed upon a 

 new leaf and worked all nig-lit before it was housed again. But before it 

 began work it spent two and one-half hours partly in wandering over the 

 leaf and partly in remaining quiet as if lost in thought as to how it was 

 to do it. 



Perhaps this was because it was at midday that he was disturbed, or 

 his organs too tender to work, for at the end of this long time he only ate 

 a round hole at the edge of the leaf twice as bis as his head and rested 

 another two hours and a half, this time quietly, then spun a strand across 

 from side to side of the slightly bellied leaf at a little more than his own 

 distance from the edge and again was quiet for another two hours, when he 

 ■was left for the night. The next morning the cut had been deepened 

 nearly to the midrib, another deep cut had been made to the midrib beyond 

 his strand and four or five more strands made from edge to edge pulling 

 the leaf over, rendering the first strand useless. It had accordingly been 

 cut at one end and dangled, crinkled up, from what was now the roof. 

 The nest, however, was now, eighteen hours after starting, by no means a 

 completed one. 



The caterpillar passes the winter in the larval stage within just such a 

 nest as it has lived in all its summer life, thoroughly lined inside with white 

 silk. In West Virginia Mr. Edwards found it full fed in July and before 



