272 INSECTS OF MASSACHUSETTS. 



yellow hairs scattered over its body, particularly on the sides, 

 where they are thickest. The general color of the whole body is 

 light blue, clear on the back, and greenish at the sides ; the head 

 is blue, and without spots ; there are two yellow spots, and four 

 black dots on the top of the first ring ; along the top of the back is a 

 row of eleven oval white spots, beginning on the second ring, and 

 two small elevated black and hairy dots on each ring, except the 

 eleventh, which has only one of larger size; on each side of the 

 back is a reddish stripe bordered by slender black lines ; and 

 lower down on each side is another stripe of a yellow color be- 

 tween two black lines ; the under-side of the body is blue-black. 

 This kind of caterpillar lives in communities of three or four hun- 

 dred individuals under a common web or tent, which is sometimes 

 made against the trunk of the trees. When fully grown they 

 leave the trees, get into places sheltered from rain, and make 

 their cocoons, which exactly resemble those of the apple-tree 

 tent-caterpillars in form, size, and materials. The moths appear 

 in sixteen or twenty days afterwards. They are of a brownish 

 yellow or nankin color ; the hind-wings, except at base, are light 

 rusty brown ; and on the fore-wings are two oblique rust-brown 

 and nearly straight parallel lines. A variety is sometimes found 

 with a broad red-brown band across the fore- wings, occupying 

 the whole space, which, in other individuals, intervenes between 

 the oblique lines. The wings expand from one inch and one 

 quarter, to one inch and three quarters. The great difference in 

 the caterpillar will not permit us to refer this species to the Neus- 

 tria of Europe, for which Sir J. E. Smith* mistook it, or to the 

 castrcnsis, which it more closely resembles in its winged form. 



Most caterpillars are round, that is, cylindrical, or nearly so ; 

 but there are some belonging to this group that are very broad, 

 slightly convex above, and perfectly flat beneath. They seem 

 indeed to be much broader and more flattened than they really 

 are, by reason of the hairs on their sides, which spread out so as 

 nearly to conceal the feet, and form a kind of fringe along each 

 side of the body. These hairs grow mostly from horizontal 

 fleshy appendages or long warts, somewhat like legs, and of which 



See Abbot's " Insects of Georgia,'' where it is figured. 



