The Scottish Naturalist 13 



At first it is pure white, and as it gets older the form of the larva 

 may be observed through the shell. As a general rule the egg 

 is placed in the centre of the gall, but I have also found it at 

 one end. 



After escaping from the egg the larva is very minute, and is 

 transparent white, with the exception of the head, which is 

 shining brownish-black. After some time this white colour 

 gives place to a beautiful shining green by the dorsal vessel get- 

 ting filled with food and its contents shining through the trans- 

 parent skin. Immediately after moulting the larvae are per- 

 fectly white, but in a short time they regain their former 

 colour. Three larvae that I watched were unable to slip the 

 old skin off the head, and perished. By the time the 

 larva has reached its third moult, it has, by eating, made a 

 considerable hollow in the gall, but the round brownish pellets 

 of frass have also accumulated, and in order to get rid of them 

 it wisely eats a round hole in one end of the gall on the under- 

 side of the leaf, and through it ejects the frass. The larvae may 

 be often observed with their heads projecting out of this hole 

 as if taking a view of the outer world, and occasionally quit the 

 galls entirely to take a short walk on the leaf, at least this is the 

 case in the breeding jar. The full fed larvae vary from ^ to 

 ^6-inch in length ; this variation being caused by the size of 

 the galls which they inhabited. The head is shining brownish 

 black, slightly narrower than the first segment of the body ; a 

 dark greenish-white stripe forms a semi-circle across the face. 

 The mouth is light-brown, the mandibles being darker at the 

 tips. The six feet are white, the claws brown; the fourteen 

 claspers are also white, but not quite so pure as in the feet. 

 The body throughout is of a dull whitish-green, without any 

 marks whatever. A few short microscopic hairs are scattered 

 over the head and body. The larvae are very sluggish 

 creatures ; when touched or alarmed in any way they beat the 

 air with the anal segment. Like most of the larvae of JVematus, 

 they carry the anus curled up under the preceding segments. 

 When ejected from the galls they, as might be expected from 

 having lived in a small round confined space, walk about in 

 short semi-circles, but full-fed larvae, who are about to spin, walk 

 much better than younger specimens. When they reach full 

 maturity they quit the galls and descend to the ground, in 



