THE LIFE-CYCLE OF CACCECIA UNIFASCIANA, DUPONCHEL. 51 



light brown, very transparent and glabrous, sprinkled with dark 

 brown dots ; behind the prothorax the larva was in colour dull 

 brownish-green, very transparent, the alimentary canal and 

 contents of intestines showing plainly, especially in the meso- 

 thorax and metathorax. Within the twelfth segment a nodule 

 of frass was noticeable as a dark olive-green patch. 



In the first instar the larva fed between two privet leaves, 

 making small round holes in the lower cuticle of the upper and 

 the upper cuticle of the lower leaf, spinning a slight web and 

 living therein. When ejected it was exceedingly active, crawling 

 at a great rate over and off the leaf ; so active in fact was it that 

 it was impossible to keep it in the field of the microscope whilst 

 the description was made, and I had to confine it in a glass 

 cell during that process. 



On August 25th the larva was in the second instar ; the head 

 was very pale brown, transparent and glabrous ; there was a black 

 spot on each side of the mouth. The prothorax was dark brown ; 

 the segments behind the prothorax were light brownish-green. 

 The length then was 3'33 mm. It was still exceedingly active ; 

 it fed only on the lower cuticle of the leaf alongside the midrib, 

 dwelling within a web ; there was no attempt to roll or spin 

 together the leaf. 



On September 5th the larva had attained the third instar ; 

 it was then 4 mm. long, the head was very transparent and 

 glabrous, very pale brown, darker round the mouth, and there 

 was a dark spot on each side of it. The prothoracic plate was 

 on the dorsum, of the same colour as the head, but at the sides 

 dark brown, almost black, equally glabrous as the head. Behind 

 the prothorax the segments were dull pale brownish-green, very 

 transparent, the alimentary canal being visible. Within the anal 

 segment a pellet of excrement showing plainly as a dark blotch. 

 The tubercles were black and rather prominent. 



By September 21st the larva had spun together a portion of 

 a dried privet leaf and prepared for hibernation inside it. On 

 October 6th my stock of larvae were put out on growing privet 

 enclosed in a muslin sleeve. On this day I found wild larvas 

 hibernating on privet in a web spun on a withered leaf which 

 was still adhering to the stem on which it grew. 



On April 5th, 1919, I took the larvae out of the sleeve and 

 started them feeding upon privet leaves in a cold room. On this 

 day I searched for wild larvae on the privet bushes but could not 

 find any. Five days later my larvae had commenced to feed upon 

 young leaves, apparently only at night, sheltering during the day 

 amongst the dead leaves amongst which they had hibernated. 

 They had greatly increased in size, were about 10 mm. long and 

 apparently almost full grown. The head was transparent and 

 highly glabrous, light brown in colour ; the prothorax was in front 

 the same colour as the head, but with a darker collar at the rear ; 



