30 [February, 



ON THE LARV^, HABITS, AND STRUCTURE OF LITROCOLLETIS 

 CONCOMITELLA, Bankes, AND ITS NEAREST ALLIES. 



BY JOUN U. WOOD, M.B. 



These notes are intended to supplement the paper by Mr. Bankes 

 which has recently appeared in this Magazine. It may be as well to 

 state at the outset that the close relationship which is so noticeable 

 in the imagos, and which has placed such obstacles in the way o£ a 

 ready recognition of the species, extends equally to the larvae, both 

 as to appearance and economy, so that until we come to consider the 

 male genitalia, we do not reach absolutely trustworthy ground. 



THE LARVA. 



Disappointing as the comparison of the special larvse may be, 

 their general life-history on the other hand, is full of interest. We 

 open the first mine thai comes to hand, it is fully formed we may be 

 sure, or it would not have caught our eye. There is nothing startling, 

 it is true, about the appearance of the larva — there it rests on the 

 floor of the mine, common-looking enough and well set up upon its 

 legs ; but had we opened this same mine in its earliest and incon- 

 spicuous state, before the leaf had become arched or distorted, there 

 would instead have met our view an ugly, helpless-looking object, 

 extremely flattened, with a huge thorax out of all proportion to the 

 rest of the body, apparently without legs, and altogether as unlike an 

 ordinary Lepidopterous larva as it is possible to conceive. But to 

 describe it more precisely : — the head, half-buried within the first 

 thoracic segment, and lying in exactly the same plane as the body, 

 points directly forwards ; it is small, very flat and thin, owing to the 

 general dorso-ventral compression, triangular in shape, and furnished 

 with large protruding jaws. The thorax tapers rapidly posteriorly ; 

 its first segment is gigantic, both as regards length and breadth, 

 and projects widely on each side of the head. The abdomen is rather 

 short, and of nearly uniform breadth. All the segments, both thoracic 

 and abdominal, are deeply divided and much flattened, the usual hairs 

 being short and inconspicuous. The legs, which might readily be 

 overlooked, are merely minute protrudable processes ; those of the 

 thorax are particularly insignificant, and quite devoid of any grasping 

 power. The head is pale brown, with the mouth parts darker, and the 

 body white. So general is the white ground-colour at this stage 

 that so far I have met with only a single exception, and this happens 

 to be one of the species we are considering, namely, concomi fella, 

 in which the colour is slightly yellowish. Markings are usually 



