THE LARVAL HABITS OF ADKINIA GRAPHODACTYLA. 175 



the larva to leave the foodplant and attach itself externally to a neigh- 

 bouring grass-culm. On the morning of the 29th the most advanced 

 larva of this plant had pupated, and a fourth larva had made its 

 appearance, this one resting lengthwise on one of the lateral stems of 

 the gentian. The work of the larva on the plant reminded one almost 

 exactly of that of Adkinia bipunctidacti/la on Scabiosa, the same 

 external evidence, but to a less extent, of the larval ravages in the main 

 or large lateral shoots, the destruction of any central shoot, and the 

 growth of the plant by means of lateral shoots which appeared to be 

 little affected by the larval attacks on the main part of the plant. 

 The most remarkable fact appeared to be the absence of any appreciably 

 hard prothoracic larval plate, suggesting boring-habits. From the very 

 first time of its external appearance, the larva had none of the characters 

 of the prothorax that one generally attaches to a boring larva, and the 

 pellucid green colour, the stiff setfe, the head and prothorax unicolorous 

 with the body, all surprisingly suggested an external- rather than an 

 internal-feeding larva, and it is probable that later examination of the 

 plant may show that the spring-used cavity allows quite free movement 

 without friction, and even the putting of the head outside among the green 

 shoots to feed. It is to be noted that, though, so far, two of the plants 

 have onh^ given up one larva each, the fact that the third plant has 

 produced four, proves absolutely that, in nature, several larvte may 

 feed in one plant. The larvte settle down for pupation almost 

 at once on becoming external, and do not wander more than 

 a few inches at most ; thej' rest head downwards, and spin the 

 anal pad in such a manner that pupation appears always to occur 

 with the larva in this position. The pupae, therefore, always hang 

 head downwards ; usually they appear to be well attached by both 

 portions of the cremaster, as described in Nat. Hist. Brit. Lepidoptera, 

 v., pp. 107-108, and then the larva has some degree of rigidity, 

 although usually the anterior portion stands well away from the 

 surface to which the cremaster is attached, and along which the adult 

 larva took up its resting-position before actual pupation, but, in one 

 case, it bangs free by the hind portion of the cremaster, and has a 

 very Nymphalid appearance in the freedom of its swing, head down- 

 wards, but it is quite clear from the structure of the venter between 

 the 8th and 10th abdominal segments, i.e., between the front and 

 hind portions of the cremaster, that this should rest firmly against 

 the attached surface, from which then the blunt-headed pupa pro- 

 trudes sHghtly, and with its green tint and faint reddish tinting reminds 

 one much of the two colours seen in all the young and growing 

 shoots of its foodplant now heading-up through the hitherto higher 

 grass by which it is apparently always surrounded, although the pale 

 lines on the wing-cases, and pale lateral Inies, are also very effective 

 on a grass-blade. On June 9th another pupa was found on the second 

 plant, and another larva ready to pupate on the third, making eight 

 larvfB from the three plants. By this date the three earliest pupie had 

 given up their imagines, a foitrth emerging on June 10th, another on 

 June 18th, another on June 14th, the pupal period being apparently 

 eleven days. 



The parallelism of the habits of the spring larvae of this species 

 with those of the larvje of Adkinia biptmrtidact>/la, described at length, 

 Nat. Hist. British Lepidoptera, vol. v., pp. 345-346, tallies in all respects 

 with the parallelism fully described {op. cit.) in the summer larvjB of 



