186 NOTES ON AGKOTIS ASHWOETHII. 



where they remain through the winter, but as soon as spring 

 has brought their food plants into leaf they come out of their 

 retreats, and begin to feed again : in five or six weeks they have 

 reached their full size, when they go under the surface of the 

 earth and make a slight cocoon, in which they change to pupae, 

 the imago appearing at the beginning of July. 



In keeping larvae of this kind in confinement it is very difiicult 

 to supply them with the conditions to which they would be ex- 

 posed in nature, and if it is attempted, by far the larger part 

 usually die during the winter. These reasons induced me to try 

 if the larvae, by being kept very warm, could not be made to 

 feed up and pupate during the autumn, and thus avoid the risks 

 attending hybernation, and in this I was more successful than I 

 anticipated, obtaining about thirty moths from some sixty eggs. 



For the first week or two after hatching I allowed the larvae 

 to feed naturally, as they are very small, compared to the size 

 they ultimately attain, and any extra heat might have proved 

 fatal ; but as soon as they had changed their skins once or twice 

 I placed them in a temperature of about 80° Fah., and they 

 quickly reached the stage in which, under natural conditions, 

 they would hybernate. The increase of temperature evidently 

 deluded the least discerning of them into the belief that the 

 appointed time had not yet arrived, and they mostly continued 

 feeding until matters had gone too far and they had perforce to 

 complete the process. Some of them, however, were not to be 

 imposed upon, and refused to feed after the proper time and 

 ultimately died ; and others, being suspicious that all was not as 

 it should be, only got on slowly, some pupating successfully 

 and others dying. By the end of September some twenty had 

 pupated, and I got about ten more through during the next 

 month. The first moths appeared in the first week in Novem- 

 ber, the rest coming out during the next four weeks, by which 

 time I had about thirty fine specimens. 



