CULTURE OF THE ROSE. 35 



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 

 20th of May anjfl 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 now 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, depositing 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 1st of June, but do not 

 usually appear in considerable numbers till the 20th 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 young slug-worms 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 yel- 

 lowish 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, immediately behind the head. 

 " The gelatinous and sluggish creatures eat the upper surface of 

 the leaf in large, irregular patches, leaving the veins and the skin 

 beneath untouched ; and they are sometimes so thick, that not a 

 leaf on the bushes is spared by them, and the vhoV 



