ACKOBASIS ANGUSTELLA. 233 



1879. (George T. Porritt, 10th July, 1879; E.M.M., 

 August, 1879, XYI, 65.) 



Cryptoblabus B1ST1UGA. 

 Plate CLYIII, fig. 2. 



For this larva, hitherto, I believe, unknown, I am 

 indebted to the Rev. Bernard Smith, of Marlow, who 

 kindly sent me, on the 12th of September, 1875, an 

 example, then no more than a quarter of an inch long, 

 within a folded oak- leaf; the leaf was, for a great 

 portion of it, quite skeletonized, and the larva after- 

 wards reduced other oak leaves to a similar condition 

 by eating holes through the substance between the 

 veins, always keeping the sides of the leaf folded to 

 within a quarter of an inch of each other by means of 

 a quantity of lightly-spun web ; I noticed that it was 

 the upper surface that was generally thus folded 

 together, though once the under surface was similarly 

 treated for a residence. 



The movement of the larva when walking is a short 

 and jerky advance, with a slight pause after every 

 step. 



On the 23rd of September it appeared to be full- 

 fed — when I secured. a figure of it, and the description 

 which follows, — and towards the end of the month it 

 spun itself up in a brownish web, half an inch long, at 

 the bottom of its cage, and the moth appeared in the 

 evening of the 4th of June, 1876. 



The full-grown larva is nearly five-eighths of an 

 inch in length, moderately slender and cylindrical, 

 though tapering a little from the third segment to the 

 head, and a little more from the eleventh to the small 

 anal tip ; the segments well divided and subdivided by 

 a transverse wrinkle on each ; the spiracular region 

 much puckered; the ventral and anal legs fairly deve- 

 loped, but placed well beneath the body. 



In colour the head and back are lightish brown, 



