PACHETRA LEUCOPH^A. 71 



when held against the light, besides minute grains of 

 frass ; they were very active and vigorous little larvae, 

 suspending themselves with fine threads and eager for 

 escape. 



The head, when a few hours old, was brown, marked 

 with black ; the body was drab at intervals, with smoky 

 dark grey-brown on the anterior segments and some 

 of the others, bearing black shining tubercles, each 

 with a black hair. On the 8th of June, when barely 

 five days old, they had grown decidedly, and their 

 colouring was now green, like that of the Poa on which 

 they had chiefly fed ; the head much marked with 

 darkish brown on the lobes, and the brown plate on 

 the second segment decidedly divided in the dorsal re- 

 gion ; dots and hairs, as before, blackish. 



On the 14th, nineteen survivors (from accidents and 

 deaths) moulted the first time ; by the 17th they were 

 green, with darker green subdorsal lines, and a lateral 

 line closely followed by a whitish spiracular stripe; head 

 and plate dotted with black, smaller tubercular dots 

 black ; by the 25th many had ceased skeletonising the 

 leaves, and had eaten the entire thickness, while some 

 had spared the midrib; by the 26th most had moulted the 

 second time, and now the head was shining pale greenish, 

 with four rather large black dots in front of the lobes ; 

 the ground colour of the back between the subdorsal 

 lines was of a rather deeper greyish-green than that on 

 the sides, but on the sides was a darker green line close 

 to the broad spiracular stripe of whitish-green; the thin 

 dorsal line and the very thin subdorsal lines were of 

 a similar whitish-green, but fainter ; the dark dots 

 of the body very small ; segmental divisions whitish- 

 green. 



At this time I put out on growing grass most of 

 those which had survived, keeping only three in closer 

 confinement for observation ; these on the 30th of 

 June were quite of a slaty-greenish colour, the pale 

 stripes and lines a little more conspicuous. 



July 5th, these had moulted the third time, and were 



