178 SPECIES NOT 



Eight days after birth they change their first 

 skin, and have now two horns, or fleshy prolon- 

 gations on the head, which are, however, at this 

 period much longer proportionally than they arc 

 afterwards. The colour is now green, like the 

 leaf of the sallow. One of these larva? died, but 

 the other continued to feed on the same leaf upon 

 which it was hatched, till the 15th. of November. 

 After feeding it always returned to rest on the 

 apex of the midrib, which was left untouched. 

 On the above day, however, it moved to the 

 axil of the leaf-stalk, and here it stretched itself 

 out at full length, with its horns porrected, appear- 

 ing as though it had taken up its winter quarters. 

 Previously to this time its attitude was sphingi- 

 form, or like that of the larva? of 41 the puss moth. 

 On the 18th. it moved again, and attached itself 

 to a cloth covering a small cage, by which it 

 was surrounded, within half an inch of the leaf- 

 stalk, its former abode. On the 27th. the leaf 

 exfoliated, as did also that on which the other 

 egg had been laid. The previous night had 

 been colder (23 F.) than any night during the 

 autumn. The larvae now enclosed itself in a web, 

 but it unfortunately died during the winter." 



The rest of the history however is well known, 

 as the larvae are found feeding on the sallow up 

 to the middle of June, when they change into 

 chrysalides, and emerge about the middle of July 

 in the imago form. The egg is totally diiferent 

 in shape from that of Sibylla, and is like one 

 of the fossil echinidoe found in the chalk, having 



