HIBERNATION OF PYRAMEIS ATALANTA. 41 



house, one Saturday afternoon in February, 1907, two or three 

 slates had become loose, and were hanging partly over the 

 gutter; these I removed, and there were the butterflies in various 

 positions clinging to the woodwork under the slates. Atalanta 

 was in a horizontal position, the head only slightly lower than 

 the body, the upper wings nearly covered by the lower pair. 

 From the difficulty in removing it, I should imaginethe hooklets 

 and spines were both firmly embedded in the tiny interstices of 

 the wood. The insect showed no signs of movement until it had 

 been in a warm room for some time, when, after a considerable 

 amount of vibration, it flew about the room. For some days it 

 fed freely off moistened sugar, but died before the spring. 



" (2) A gardener trimming a thick holly hedge near by in 

 January, brought to me a holly branch on which were two 

 sleeping G. rhamni, both males. The hedge was a very old one, 

 and the dead leaves had accumulated in a thick mass through 

 the middle, forming a rainproof covering to the lower portions, 

 from which the rhamni were taken. The day following the 

 gardener called me to look at another kind of butterfly in the 

 same hedge. This turned out to be a very fine female atalanta, 

 fixed head downwards on a dead leaf under the thick covering 

 already mentioned. At the same time I found a female rhamni 

 also attached to a dead leaf, which it very closely resembled. 

 The last time I saw atalanta at rest was under the eaves of my 

 house in early November, 1908. A week later when I went to 

 examine it, I found only three wings, the insect had evidently 

 been devoured. All three atalanta were females, and the position 

 taken up was different in each case." 



The following notes are from Captain Purefoy's observations, 

 with which he has been good enough to supply me. 



" The summer and autumn of 1908 were chiefly devoted by 

 us to experimenting with this insect (atalanta). Most of October 

 was very warm, and atalanta had fine opportunities of feeding 

 up. When the weather turned cold certainly a number of the 

 insects became quite torpid while clinging to bark, which they 

 greatly resembled. They remained very exposed, but not more 

 so than G. album. Both at Christmas and in January, and 

 again in March, they met with terrible weather. Twice the 

 whole roof nearly collapsed under the weight of snow, and the 

 temperature dropped to zero. But for the exceptional cold I am 

 sure that at least a dozen insects would have survived our long 

 winter. We started with about a hundred. As it was, two 

 beauties were seen flying strongly in February, and three others 

 actually survived the whole winter. They worked out their own 

 salvation. 



" The female atalanta is the strongest and most vigorous 

 butterfly I know, and, although our winter climate is unsuited 

 to the species, I am sure that an occasional female does survive, 



ENTOM. — FEBRUARY, 1913. E 



