314 INSECTS OF MASSACHUSETTS. 



stripe, also marked with three black lines, on each side ; and the 

 head, fore-legs, and spiracles are black. When fully grown, 

 these caterpillars measure about an inch and a half in length. 

 They live together, in swarms of twenty or more individuals, in 

 a nest made of a single leaf folded or curled at the sides, and 

 lined with a thin web of silk. An opening is left at each end of 

 the nest ; through the lower one the dirt made by the insects falls, 

 and through the upper one, which is next to the leaf-stalk, the 

 caterpillars go out to feed upon the leaves near to their nests. 

 When young they sometimes fold up one side of a leaf for a nest, 

 and eat the other half. The stalks of the leaves, to which their 

 nests are hung, become covered with silk from the threads carried 

 along by the caterpillars in going over them ; and these threads 

 help to secure the nests to the branches. They eat all parts of 

 the leaves except the stalks and larger veins, and frequently strip 

 long shoots of their foliage in a very few days. Towards the end 

 of September or early in October, according to the age of the 

 different broods, they descend from the trees, disperse, and seek 

 a shelter in crevices or under leaves and rubbish on the ground, 

 where they make their cocoons. These are thin irregular silken 

 webs, so loosely spun that the insects can be seen through them ; 

 but they are protected by their situation, or by the dead leaves and 

 other matters under which they are made. As soon as the 

 cocoons are finished, the insects become chrysalids, and remain 

 quiet through the winter ; and about the middle of June, or 

 somewhat later, they are transformed to moths. They belong to 

 the genus Clostera, or spinner, so named on account of the 

 spinning habits of the caterpillars. The antenna? are narrowly 

 feathered or pectinated in both sexes ; the thorax has an elevated 

 crest in the middle ; the tail is tufted and turned up at the end, in 

 the males ; the fore-legs are thickly covered with hairs to the 

 end, and are stretched out before the body when the insect is at 

 rest. Our poplar spinner may be called Clostera Americana, 

 the American Clostera. It closely resembles the European ana- 

 stomosis, from which, however, it differs essentially in its cater- 

 pillar state, and the moth presents certain characters, which, on 

 close comparison with the European insect, will enable us to dis- 

 tinguish it from the latter. It is of a brownish gray color ; the 



