210 INSECTS OF MASSACHUSETTS. 



The Hawk-Moths (Sphinges) generally have the antennas 

 thickened in the middle, and tapering at each end, and most often 

 hooked at the tip ; the wings are narrow in proportion to their 

 length, and are confined together by a bristle or bunch of stiff 

 hairs on the shoulder of each hind-wing, which is retained by a 

 corresponding hook on the under-side of each fore-wing ; all the 

 wings, when at rest, are more or less inclined like a roof, the up- 

 per ones covering the lower w r ings ; there are two pairs of spurs 

 on the hind-legs ; a few fly by day, but the greater number in the 

 morning and evening twilight. 



In the Moths (P 'halesna) the antennas are neither knobbed at 

 the end nor thickened in the middle, but taper from the base to 

 the extremity, and are either naked, like a bristle, or are feathered 

 on each side ; the wings are confined together by bristles and 

 hooks, the first pair covering the hind-wings, and are more or less 

 sloping when at rest ; and there are two pairs of spurs to the hind- 

 legs. These insects fly mostly by night. 



I. BUTTERFLIES. {Papilioncs.) 



Besides the characters already given, which distinguish this sec- 

 tion of the Lepidoptera, it may be stated that their caterpillars 

 always have sixteen legs, namely two, which are tapering, jointed, 

 and scaly, to each of the first three segments behind the head, 

 and a pair of thick fleshy legs, without joints, to all the remaining 

 segments, except the fourth, fifth, tenth, and eleventh. 



The butterflies are divisible into two tribes ; namely, the true 

 butterflies, which carry all their wings upright when at rest ; and 

 the skippers, which have only the fore-wings upright, the hind- 

 wings being nearly horizontal when at rest. 



1. Butterflies. 



In these insects, all the wings are erect when at rest, and the an- 

 tennae are knobbed, but never hooked, at the end. Their cater- 

 pillars have a head of moderate size, suspend themselves by 

 the tail when about to transform, and are not enclosed in co- 

 coons. Some of these butterflies have the six legs all equally fit- 

 ted for walking ; their caterpillars are more or less cylindrical, and 



