COMPLETION OF THE LIFE-HISTORY OF LYC^ENA ARION. 147 



last moult, measures j^^ in. long. This remarkable caterpillar 

 passes over ten months of its existence in its last stage, and 

 that is after its third moult, as upon a careful microscopical 

 examination of all structural detail, I find every part absolutely 

 unchanged, which accounts for its extremely small head, which 

 is out of all jjroportion to the size of the larva, and only propor- 

 tionate soon after the third moult, when it measures only ^ in. 

 long. The small black dorsal disc on the first segment now 

 appears as a mere speck. The head is set on a very flexible 

 retractile neck which can be readily protruded beyond the first 

 segment while the larva is in motion ; but when resting, the 

 head is completely hidden and withdrawn into the ventral sur- 

 face of the segment. Dorsal view : Both anterior and posterior 

 segments are rounded, the body gradually increasing in width to 

 the tenth segment. The segmental divisions are deeply cut, 

 each segment being laterally convexed. Side view : First 

 anterior and last three posterior segments somewhat flattened 

 dorsally and projecting laterally ; second to ninth segments 

 humped dorsally ; the medio-dorsal furrow usual to Lyccena larvae 

 is, in avion, only indicated on the posterior half of each segment; 

 the sides are sloping and convoluted to the spiracles ; the lateral 

 ridge is dilated, swollen, and prominent, but rounded, and the 

 ventral surface is full and of a bulbous character ; the rather 

 small feet are well provided with strongly-curved hooks. All 

 other structural details are as in the description given of the 

 larva after third moult in vol. xxxii. p. 105. But on examining 

 the full-grown specimen, I find that all the long dorsal hairs 

 have been broken or worn off short, leaving only a series of 

 basal stumps. 



The colour is a pale creamy ochreous, with a pinkish lilac 

 tinge along the lateral ridge and surrounding both the first and 

 last segments. When first found, the entire skin had a shining 

 distended appearance, as if too tight for its obese proportions. 

 Although I have not yet been able to ascertain its actual food 

 or manner of feeding, I think there is but little doubt that 

 it is tendered by the ants (Lasius Jiavus), in the same way 

 as their own larvae are fed from mouth to mouth with food the 

 ants disgorge. This point of its life-history I hope to clear up 

 later on. 



The larva described pupated on the surface of the ground, 

 free of web, on the evening of June 10th. At first the pupa is a 

 clear pale apricot-yellow, which very gradually deepens to a 

 dark amber colour, excepting the wings, which remain light 

 ochreous. 



June, 1906. 



o2 



