﻿LÉPIDOPTÉROLOGIE COMPAREE 299 



EXPLANAllON Ol' PLATES 



FiG. I and 2. — Dorsal and latéral vieus of ihc larva of Lycacna alcoii, 

 when it leaves the Gentian, in the third instar, about 

 3 mm. long, enlarged x 6 (PI. DI ; fig. 4178, 417g). 



I-'IG. 3 and 4. — Dorsal and latéral views of the larva in Novcmbcr, 

 when it has grown to 5 mm. long, x 6 (PI. DI ; fig. 4180, 

 4181). 



\\'hen full grown in June, it has the same head, plates 

 and hairs, but the skin is so stretched and attcnuated as 

 to hâve only a faint pink colour, and the fat-bodies, dorsal 

 vessel etc. are almost as distinct as if there were no skin. 

 I failed to gct this drawn, as a mistaken prepossession 

 made me expect a moult to occur almost immediately. 



Fig. 5 and 6. — Ventral and latéral views of the pupa ; increascd (PI. DI ; 

 fig. 4182, 4183). 



Fig. 7. — Eggs of L. alcon, x 20. 



Fig. 8. — Larva of L. nie on, first stage (in Farrants' médium), x 40. 



Fig. q. — Skin of larva of L. alcon, first stage, x 40. 



Fig. 10. — Skin of larva of L. alcon, second stage, x 20. 



Fig. II. — Skin of larva in second stage, x 40. 



Neither fig. 11 or 12 is satisfactory, but together they 



show the plates, hairs, lenticles, honc^'-gland etc. 



adequately. 



Fig. 12. — Skin of larva in third stage, x 20. 



Fig. 13 and 14. — Thèse are the skins of the larva that showed a fourth 

 instar; fig. 13 is the third stage skin that w^as about to be 

 moulted. Fig. 14 is the fourth stage skin that was 

 beneath it, both x 20. 



Incidentally it may be noted that the skin in fig. 13 is 

 very clean, there being no larval tissues to be removed 

 from its' inner surface, thèse ail being removed in the new 

 skin beneath it. This désirable efFect is secured when 

 the moult is very imminent, and manipulations are 

 successful, as hère, otherwise the resvilt is usually that 

 both skins are spoilt. 



