POLYOMMATUS (LYC^ENA) AGESTIS. 119 



The pot containing the larvae and the various plants 

 was kept entirely uncovered inside a window of 

 western aspect ; the grasses were much grown by the 

 7th of March, 1878, when I could only see two larvae 

 on a new shoot of their food, and on the 14th only one, 

 whereupon I began to cut down the grass (a blade at 

 a time) carefully, so as to lay bare the few new scat- 

 tered shoots of Helianthemum, which were from one to 

 two, or three inches above ground, and very near the 

 margin of the pot. On the 21st, the second larva was 

 again visible on a little shoot close to the earth, and 

 two more larvae, less advanced, on other small shoots, 

 were seen on April 14th. 



Here it may be proper to state the fact, that after 

 hibernation, neither of the larvae fed at all on any of 

 the mature sprays of the plant, which seemed appa- 

 rently healthy and vigorous, but pertinaciously sought 

 the young tender shoots, eating a portion from under 

 a leaf, then a little from another leaf, or moved away 

 entirely, creeping over the ground and through all 

 impeding growths, until, with unerring instinct, 

 another shoot, sooner or later, was reached ; thus I 

 was continually losing sight of one or more of the 

 larvae often for days together, but only to find them 

 again by the aid of new blotches appearing to betray 

 them. 



Towards the end of April they ravaged so recklessly 

 the small stock of their food remaining in the pot, 

 never staying to clear the whole underside of a leaf, 

 but changing their quarters so often that I began to 

 fear they would desert the pot and escape altogether. 

 At that time I was unable to obtain a fresh supply of 

 their food, and to make sure of completing my obser- 

 vations of the larva when full grown, I confined the 

 two largest individuals in a bottle, and supplied them 

 with cut portions of their food, on which they throve, 

 and therein attained their full growth of barely half an 

 inch ; and on the 15th of May one fixed itself for pupa- 

 tion by a cincture across the back of the fourth seg- 



