INSECTS. 329 



first two pairs of legs are brownish-gray, or dirty white, except 

 the thighs, which are almost entirely black. The hind legs 

 are black, with whitish knees. The wings are smoky, and 

 transparent, with dark-brown veins, and a brown spot near the 

 middle of the edge of the first pair. The body of the male is 

 a little more than three twentieths of an inch long, that of the 

 female one fifth of an inch or more, and the wings expand 

 nearly or quite two fifths of an inch. These Saw-flies come 

 out of the ground, at various times, between the twentieth of 

 May and the middle of June, during which period they pair 

 and lay their eggs. The females do not fly much, and may be 

 seen, during most of the day, resting on the leaves ; and, when 

 touched, they draw up their legs, and fall to the ground. The 

 males are more active, fly from one rose-bush to another, and 

 hover around their sluggish partners. The latter, when about 

 to lay their eggs, turn a little on one side, unsheathe their 

 saws, and thrust them obliquely into the skin of the leaf, depos- 

 iting, in each incision thus made, a single egg. The young 

 begin to hatch in ten days or a fortnight after the eggs are 

 laid. They may sometimes be found on the leaves as early as 

 the first of June, but do not usually appear in considerable 

 numbers till the twentieth of the same month. How long they 

 are in coming to maturity, I have not particularly observed ; 

 but the period of their existence in the caterpillar state proba- 

 bly does not exceed three weeks. They somewhat resemble 

 the young of the Saw-fly, in form, but are not quite so convex. 

 They have a small, round, yellowish head, with a black dot on 

 each side of it, arid are provided with twenty-two short legs. 

 The body is green above, paler at the sides, and yellowish be- 

 neath ; and it is soft, and almost transparent, like jelly. The 

 skin of the back is transversely wrinkled, and covered with 

 minute elevated points ; and there are two small, triple-pointed 

 warts on the edge of the first ring, immediately behind the 

 head. These gelatinous and sluggish creatures eat the upper 

 surface of the leaf in large irregular patches, leaving the veins 

 of the skin, beneath, untouched ; and they are sometimes so 

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