THE ENTOMOLOGIST. O 



each of the 4ih and 5th segments, the spots on the 5lh seg- 

 ment being nnich smaller and encircled by a thin black ring; 

 the black rings, however, in some instances are absent 

 altogether : others, on arriving at the adnlt state, instead of 

 having the ordinary horseshoe-like plate on the back of the 

 2nd segment, possess two squarish-shaped patches of a dark 

 pitchy brown. This species, in common with all other leaf- 

 mining Tenthredo caterpillars with which I am at present 

 acquainted, though amply furnished with organs of loco- 

 motion, evinces no inclination to leave one leaf and enter 

 another ; but should the supply of food fall short of the 

 creature's requirements, in consequence of the leaf being 

 peopled by too many larvae or from any other cause, it quits 

 the leaf, and in time there is produced a proportionally small 

 imago. When it has become full-fed it casts its skin for the 

 last time, and then this last-thrown-ofF tegument may often 

 be seen lying inside the blotched leaf, retaining its shape as 

 though the larva had not quilted it. When full-grown the 

 body has a yellowish tone, its mouth is brown, the eye-spots 

 are black, and on the dorsal surface of some of the segments 

 four dusky marks, are perceptible as they faintly shadow 

 themselves through the skin, the posterior pair of these dusky 

 markings being the largest ; some individuals, however, differ 

 with respect to these markings, their 6th, 7th, 8th, 9lh, 10th, 

 11th, l*2lh and 18th segments having only one dusky mark, 

 and that situated at the base of each of the above-mentioned 

 segments: when irritated at this period of its existence the 

 larva partially curls up its body, but straightens itself the 

 next instant : no emission of fluid has been observed to pro- 

 ceed from its spiracles. The full-grown larva averages from 

 9 to lOg- lines in length. After remaining in its mine in an 

 inactive stale for a time, it bites a hole either in the upper or 

 under skin of the leaf, and falls to the ground ; never under 

 any circumstances has it been observed to construct its 

 cocoon inside the mined leaf; it always enters the ground to 

 undergo pupation : the caterpillars of the first brood con- 

 tinue feeding till about the middle of June. After the larva 

 of the first brood has laid in its cocoon for a certain period 

 its body becomes dull white, and at the appointed time it 

 passes slowly into the pupa form; the body is then usually 

 of a yellow colour, but the bodies of some pupae are of an 



