THE EUROPEAN PINE SAW-FLIES. 521 



thorax; her body beneath and her legs are paler, of a 

 dirty leather-yellow color ; and her wings resemble those 

 of the male. Her antennae are short, taper to a point, 

 consist of nineteen joints, and are toothed on one side like 

 a saw. My specimens of this kind of saw-fly, which were 

 raised from the caterpillars in the summer of 1838, came 

 out of their cocoons towards the end of July in the same 

 year; but I have also found them on pines and firs early 

 in May. 



The European pine saw-flies lay their eggs in slits which 

 they make with their saws in the edges of the leaves ; and 

 it is probable that our fir saw-flies proceed in the same way. 

 In June and July the false caterpillars of the latter may 

 be found on firs ; and, according to notes made by me 

 many years ago, the same insects, or some very much like 

 them, were observed on the leaves of the pitch-pine also. 

 They are social in their habits, living together in consid- 

 erable swarms, and so thick that sometimes two may be 

 seen feeding together on the same leaf, and sitting opposite 

 to each other. In order to lay hold of the leaf more firmly, 

 they curl the hinder part of the body around it; and, if 

 they are disturbed, they throw up their heads and tails 

 with a jerking motion. When fully grown, they are from 

 five to six tenths of an inch in length; they are nearly 

 cylindrical in form, thickest before the middle, and tapering 

 behind, and have twenty-two legs. The head and the first 

 three pairs of legs are black. The body is of a pale and 

 dirty green color above, with a light stripe along the top 

 of the back, separating two of a darker-green color; there 

 are two dark green stripes on each side of the body; and 

 the belly and prop-legs are yellowish. When young, the 

 two stripes on the back are much darker, and those on 

 the sides are nearly black. The skin, though covered with 

 very fine transverse wrinkles, is not rough, and with a 

 magnifying-glass a few short hairs may be seen scattered 

 over it. After the last moulting their color fades, and they 

 66 



