264 BRITISH BUTTERFLIES. 



rather large leaf. This is the only time this has been observed, 

 though several times a larva has been seen as far in the leaf as the 

 2nd abdominal segment. It is, however, exceptional rather than the 

 rule for them to engage only the head and extensile neck (Id.). 



The following account of the habits of the hybernated larva is from 

 the pen of Prof. Zeller, and appeared in the course of an article 

 published by him in the Ent. Mo. Mar/, for September, 1867. — On 

 February 14th I searched for the.' larvae which had survived the winter 

 in order to put them again in the sunshine. In the flower-pots which 

 had been exposed to the open air I found both the plants and the larvae 

 were dead ; in the third flower-pot I found fifteen larvae, of rather 

 different sizes ; they had sat motionless the whole time, either on the 

 stems of grass, or on or under living leaves of Erodium. ... Of 

 the fifteen larva3 seven died by degrees. . . . Having planted 

 three vigorous plants, the remaining larva? prospered so well, that by 

 April 8th, I could look upon them as quite, or almost quite, full-grown. 

 They devoured the primate leaves — gnawed the stem of the leaf, hence 

 causing the upper part to wither, and did not spare the young shoots, 

 when the plants assumed at last a very injured appearance, and were 

 abundantly sprinkled with grains of brown-green excrement. The 

 larvae crawl very slowly, whilst they spin a white thread, which they 

 fasten to the right and left, and on which they place their legs. They 

 are not easily perceptible on the food plant, since they are the same 

 shade of green, and even their bristles have the same colour as the 

 hairs on the leaf -stalk (Zeller). 



Ontogeny of Larva. — First instar (September 18th, 1877) : Very 

 minute with a glistening blackish head, stoutish body, of a light drab- 

 green colour, velvety and hairy. Eight days old : Its size is now 

 doubled. One month old: Of the usual Lycaenid shape, 2mm. in 

 length, thick in proportion, with small retractile head, the body of a 

 dull pinkish-brown colour, with darker dorsal stripe and rather hairy. 

 After liybernation (early in March) : Of a dingy slaty-green colour ; it 

 moults in early March. Penultimate instar: Quite pale green on the 

 back, broadly pinkish along the lateral ridge and still hair}\ In early 

 April it is about 3mm. in length, of greenish flesh-colour, palest on 

 the prothorax and dorsal eminences, pinkish in the dorsal hollow, and 

 also beneath the spiracular region, the long whitish hairs closely 

 resembling those of the foodplant. Final moult took place on April 

 21st. Final instar: About 12mm. in early May when full grown. 

 Like that of artaxerxes except that the green colour is more lively and 

 full, and the pink along the lateral region is darker, inclining to 

 purplish. Final instar of var. artaxerxes (May, 1868): About 8mm. 

 long on May 8th, becoming 12mm. long by May 18th. At the earlier 

 date pale green in colour, clothed with very fine and short whitish 

 bristles. Of the usual Lycaenid shape, short and thick, arched on the 

 back, down which are two rows of rather peaked cone-like eminences, 

 with a dorsal hollow between them ; the prothorax simply rounded 

 above, and rather longer than the others, tapering a little near the 

 head, which is very small and retractile ; the anal segment tapers very 

 little, is rounded behind and hollowed above on the sides, the 8th 

 abdominal has a small but prominent wart on each side. The dorsal 

 line beginning on the metathorax and ending on the 8th abdominal is 

 faint brown in colour, wider and more strongly marked just at the 



