DIMORPHA VERSICOLORA. 245 



moss, leaves, or other debris, to spin their cocoons (Gascoyne). 

 One of 10 eggs hatched on May 6th, 1858, the young larva took 

 short excursions on the twig and returned to the other eggs, by next 

 morning two more eggs had hatched, the three larvae sitting together 

 under a leaf, on the 8th none came out, but by the 9th another had 

 emerged, and on the 10th a fifth left the egg and they all moved to 

 another leaf, still keeping to the underside and near the leaf-stalk ; 

 the fifth, however, was not very sociable and died on the 15th. 

 The young larvae take up a position at rest perhaps rather ap- 

 proaching that of Lophopteryx camelina than that of Sphinx, only 

 with the head not quite so far turned back, and with a smaller part 

 of the posterior end of the body attached to the leaf. The larvae 

 appear to feed chiefly (certainly not exclusively) by night ■ from the 

 first they have, in eating, attacked a leaf sideways, biting through 

 the whole substance. On May 24th, three of the larvae changed their 

 first skins, the other the next day • they still rested under the leaf 

 but fed rapidly in the sunshine, and maintained strictly their gre- 

 garious habit, resting in actual contact, crawling or stretching 

 forward to the edge of the leaf when hungry ; they are very econo- 

 mical feeders, wasting nothing, but, after eating the nearer part of 

 a leaf, they attack the distant part, and, having eaten until 

 the piece on the outer edge is almost detached, they stretch out to 

 their utmost, nibble away at the outlying piece till it is so narrow 

 that they can get the extremity into their mouths and munch it away 

 as Kentish men do a stick of celery ; they were again noticed 

 feeding at dusk, also later at about 10 p.m. On the evening of June 

 2nd they again moulted, and two again on the 9th, and two on the 

 10th, and in their 4th stadia were about an inch long when not 

 stretched out; on the 14th they were transferred to a breeding-cage 

 and completed their development there. In nature the habits were 

 further observed on July 2nd — 3rd, 1858, at Green Trees Forest, when, 

 by turning back the branches of the smaller birches that had evidently 

 been well eaten, so as to see the undersides of the leaves, the 

 whitish backs of the larvae (which made them very conspicuous) were 

 also exposed to view ; the larvae were most abundant on 

 bushes of from 2 ft. to 6 ft. high, and affected the middle and lower 

 branches quite as much as the upper, eating off whole leaves, 

 sometimes also leaf-stalks. They appear to be more or less gre- 

 garious to the last, usually more than one is found on a tree, 

 on one occasion 7, and on another 5, nearly fullgrown larvae were 

 found upon a little tree, not 3 ft. high, two on the same twig, and 

 within an inch of each other. Although generally adhering so closely 

 to their resting-place, they sometimes fling themselves off like a larva 

 of Cucullia verbasci. They become fullfed from about July 9th (Merri- 

 field). Poulton notes ( Proc. Ent. Soc. Loud., 1892, p. xv) that, in the 

 second stadium, " the larvae arrange themselves in small groups 

 upon the leaves and leaf-stalks of the birch, and when disturbed they 

 raise the anterior part, bending the head over the dorsal surface of 

 the posterior part of the body. In this attitude they strongly re- 

 mind the observer of those Tenthredo larvae, which, when irritated, 

 bend the tail forwards over the anterior part of the body ; the fact 

 that the head is raised in the one and the tail in the other does not 

 cause any conspicuous difference when the larvae are seen from a little 



