184 THE entomologist's record. 



the valves. The cases being clean and white would support the 

 contention that they were not fully complete, as in this species I have 

 found the white colour rapidly becomes a dirty brown. On these cases 

 it was interesting to note the vestigial remains of the earlier stage of 

 case-growth. On each side of the " mouth " end somewhat behind the 

 " neck " of the case were the two halves of this early case, very small, 

 but very distinct, noticeable by their dirty brown colour contrasting 

 with the clean Avhite of the new material. The earlier case had 

 apparently been split down the ventral side, and partly down the back, 

 the two " wings " as it were being incorporated in the new tube, which 

 the larva had made, and subsequently new rings of tube-wall substance 

 added in front to form a suitable mouth-opening for the case. In an 

 older weathered case one does not easily recognise this early remnant. 

 This sized case was apparently that in which the larva was to pass its 

 last stage, and in which it was to pupate. The mouth opening turns 

 down considerably so tha't the normal position of the case is 20° or 

 less to the plain of attachment when the larva is at rest. The " neck " 

 of the case has a more graceful curve than in many species and the 

 margin of the mouth opening is turned outwards. As the neck is 

 longer than in most species, the case appears to be at a greater angle to 

 the plain of attachment more than it really is. Although the food 

 plant of this species is abundant everywhere the insects are extremely 

 local, but when found one can, as a rule, depend upon finding a 

 considerable number. The larvae feed on the undersides of the leaves, 

 and since these are very thick one does not easily see the blotches they 

 make unless one searches on hands and knees and braves the stout 

 defensive weapons of the plant. 



The following is a description of a larva, taken on September 29th, 

 1904, when it was presumably in its final instar. 



" The head, brown not black, very shiny, much more so than the 

 plate on the first thoracic segment. 



First thoracic segment, with a large dorsal plate, very dark in 

 colour, almost black, with a very fine suture up the middle, which 

 gradually becomes finer, almost vanishing at the front margin of the 

 plate. 



The second thoracic segment has four small plates arranged in an 

 almost straight line transversely to the body of the larva, the front 

 margins of the four forming a very slight curve, concave towards the 

 first segment. These four plates are, to speak very roughly, of a 

 general right-angled triangle shape, the two centre plates with their 

 right-angles approximating towards the rear, and each with one acute 

 angle at the front margin, while the two outer ones have their right- 

 angle nearest the sides of the segment in front, hence most of the 

 front margin of the plates is formed by these two. The central suture 

 is somewhat apparent, while the two oblique sutures, flankeil by the 

 approximating hypotenuses of the two triangles are scarcely observable 

 when th(! larva is at rest, but become easily visible when the larva is 

 active and the segments are extended in movement. 



The third thoracic segment has two small elliptical plates lying at 

 right angles to the longitudinal line of the body, and in line with tho 

 side-margins and rear angle of the outer triangular plates of the 

 second segment, consequently they are very wide apart, and lie about 

 midway between the fore and aft margins of the larval segment. 



