314 PROCEEDINGS OF THE 



glutinous substance ; but where it gets this I cannot conjecture. 

 AVhen young, the two surfaces of the fold touch one another, but 

 as the larva grows it gets more open, and it then ver}^ often 

 becomes tenanted by plant lice. I have also found a small lepi- 

 dopterous larva in these folds. 



When young the larva is whiteish, with the markings not very 

 distinct. At the third moult the head is flattish, sloping towards 

 the mouth; in breadth, about the same as the second segment; 

 the colour blackish, fuscous, yellow, or brownish-yellow, with the 

 eyes and mouth black. The feet are greenish-white, with brown 

 claws; over each is a broad black band ; the fourteen claspers are 

 whiteish. The body is greenish-white; the food-canal giving it 

 a darker tint. The skin is beset with many small tubercles, each 

 ending in a short hair; at the sides the segments project in ridges. 

 Over the last segment are two — often onty one — broad black 

 bands, of a variable size and distinctness; the anal cerci black. 



Previous to spinning the head is, as a rule, of a lighter colour, 

 and often there is a distinct black splash on the face; the anal 

 marks are very faint; and the body yellowish-white. The length 

 is from 5-7 lines. 



The larva carries the body in a somewhat arched position pos- 

 teriorly, the anus touching the leaf.'' In the autumn, when it 

 becomes full fed, it drops to the ground, and spins a light, brown 

 cocoon, in wliich it remains unchanged till May, when it becomes 

 a pupa, in which state it remains ten or twelve days. 



The pupa is green. 



I believe I have correctly identified this species with the N. 

 crassulus, Thoms.; but with regard to the other names I have quoted 

 above, I am not sure whether they are synonymous, or if they 

 refer to distinct species. My Possil specimens differ from a type 

 of leucostidus that I got from Herr Brischke, of Danzig, in having 

 the legs yellowish, instead of white; the femora are (apparently) 

 thicker; and the stigma, at the apex, is darker than at the base; 

 the stigma being, in my specimen of leucmtlchis, of a uniform white 

 colour. Kaltenbach's description of the larva of xantliogaster, is 

 not quite in accordance with mine (but this may be owing to his 

 not having described it in full); while Foerster's description (of 



* It commences feeding by eating the epidermis, near wliere the e(^<^ was 

 placed; then in scattered places all under the fold, and ultimately over the 

 whole leaf. It never devours the leaf ([uite through. 



