LEPIDOPTERA. 283 



sparingly clothed with long and fine yellow hairs on the sides 

 of the body, and having four short and thick brush-like yel- 

 lowish tufts on the back, that is on the fourth and three follow- 

 ing rings, two long black plumes or pencils extending forwards 

 from the first ring, and a single plume on the top of the eleventh 

 ring. The head, and the two little retractile warts on the ninth 

 and tenth rings are coral red; there is a narrow black or brown- 

 ish stripe along the top of the back, and a wider dusky stripe 

 on each side of the body. These pretty caterpillars do not 

 ordinarily herd together, but sometimes our apple-trees are 

 much infested by them, as was the case in the summer of 

 1828. In the summers of 1848, 1849, and 1850, they were 

 very numerous on trees in Boston, both in private yards and 

 on the Common, where the horsechestnuts, which seem ordi- 

 narily to escape the attacks of insects, were almost entirely 

 stripped of their leaves by these insects. When they have 

 done eating, they spin their cocoons on the leaves, or on the 

 branches or trunks of the trees, or on fences in the vicinity. 

 The chrysalis is not only beset with little hairs or down, but 

 has three oval clusters of branny scales on the back. In about 

 eleven days after the change to the chrysalis is effected, the 

 last transformation follows, and the insects come forth in the 

 adult state, the females wingless, and the males with large 

 ashen gray wings, crossed by wavy darker bands on the upper 

 pair, on which, moreover, is a small black spot near the tip, 

 and a minute w^hite crescent near the outer hind angle. The 

 body of the male is small and slender, with a row of little 

 tufts along the back, and the wings expand one inch and three 

 eighths. The females are of a lighter gray color than the 

 males, their bodies are very thick, and of an oblong oval shape, 

 and, though seemingly wingless, upon close examination two 

 little scales, or stinted w^nglets, can be discovered on each 

 shoulder. These females lay their eggs upon the top of their 

 cocoons, and cover them with a large quantity of frothy mat- 

 ter, which, on drying, becomes white and brittle. Different 

 broods of these insects appear at various times in the course 

 of the summer, but the greater number come to maturity and 

 lay their eggs in the latter part of August, and the beginning 



