144 



PAESONS ON THE EOSE. 



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 paii\ The body of the 

 male is a little more thaa 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 j)eriod 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, de- 

 positing 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 ap- 

 pear in considerable numbers until 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 probably 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, and are provided with twenty-two short legs. 

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

 beneath ; 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, immedi- 

 ately behind the head. These gelatinous and sluggish 



