LEPIDOPTERA. 275 



be^in to provide a shelter for themselves, by covering the upper 

 side of the leaf with a web, which is the result of the united 

 labors of the whole brood. They feed in company beneath 

 this web, devouring only the upper skin and pulpy portion of 

 the leaf, leaving the veins and lower skin of the leaf untouched. 

 As they increase in size, they enlarge their web, carrying it 

 over the next lower leaves, all the upper and pulpy parts of 

 which are eaten in the same way, and thus they continue to 

 work downwards, till finally the web covers a large portion of 

 the branch, with its dry, brown, and filmy foliage, reduced to 

 this unseemly condition by these little spoilers. These cater- 

 pillars, when fully grown, measure rather more than one inch 

 in length ; their bodies are more slender than those of the other 

 Arctians, and are very thinly clothed with hairs of a grayish 

 color, intermingled with a few which are black. The general 

 color of the body is greenish yellow dotted with black; there 

 is a broad blackish stripe along the top of the back, and a 

 bright yellow stripe on each side. The warts, from which the 

 thin bundles of spreading, silky hairs proceed, are black on the 

 back, and rust-yellow or orange on the sides. The head and 

 feet are black. I have not observed the exact length of time 

 required by these insects to come to maturity; but towards 

 the end of August and during the month of September they 

 leave the trees, disperse, and wander about, eating such plants 

 as happen to lie in their course, till they have found suitable 

 places of shelter and concealment, where they make their thin 

 and almost transparent cocoons, composed of a slight web of 

 silk intermingled with a few hairs. They remain in the cocoons 

 in the chrysalis state through the winter, and are transformed 

 to moths in the months of June and July. These moths are 

 white, and without spots; the fore thighs are tawny yellow, 

 and the feet blackish. Their wings expand from one inch and 

 a quarter to one inch and three eighths. Their antennse and 

 feelers do not differ essentially from those of the majority of 

 the Arctians, the former in the males being doubly feathered 

 beneath, and those of the females having two rows of minute 

 teeth on the under side. This species was first described by 

 me in the seventh volume of the "New England Farmer," 



