POLYOMMATUS (LTO^ENA) AGESTIS. 121 



are but one species.* (W. B., 4, 2, 79 ; E.M.M. XV, 

 241.) 



POLYOMMATUS (LYC2ENA) AGESTIS {MeDON), VAR. 



Artaxerxes. 

 Plate XVI, fig. 1 (1 b, 1 c, 1 d, 1 e, 1 g). 



On the 8th May, 1868, Mr. Doubleday kindly pre- 

 sented me with the larvse of Artaxerxes, about half 

 grown, which had been sent to him by Mr. Wilson, of 

 Edinburgh, who found them on Helianthemum vulgare. 



They fed well on this plant, and were always on the 

 undersides of the leaves, to which they assimilated so 

 well as to be difficult of detection. 



The larva is of the usual Lyccena shape, somewhat 

 onisciform, short and thick, being arched on the back, 

 sloping on the sides, the spiracular region swollen 

 and projecting laterally much beyond the ventral 

 prolegs. The segments appear deeply divided, espe- 

 cially on the back, down which are two rows of rather 

 peaked cone-like eminences, with a dorsal hollow 

 between them ; the second segment simply rounded 

 above, and rather longer than the others, and tapering 

 a little near the head, which is very small and retrac- 

 tile ; the anal segment tapers very little, is rounded 

 behind and hollowed above on the sides ; the twelfth 

 segment has a small but prominent wart on each side. 



The half-grown larva is from three to four lines in 

 length, pale green in colour, and clothed with very 

 fine and short whitish bristles. The dorsal line 

 beginning on the fourth and ending on the twelfth 

 segment is of a faint brown, though wider and more 

 strongly marked just at the beginning of each seg- 

 ment, and widest at its termination on the penulti- 

 mate. 



* [The elaborate notice of the two reputed species by the late George 

 "Wailes, in his " Catalogue of the Lepidoptera of Northumberland and 

 Durham," published in the ' Transactions of the Tyneside Naturalists' 

 Field Club for 1858/ vol. ii, part 4, p. 189, should here be noted.— H.T.S.] 



