1903.] 215 



AN EXPERIENCE IN INTERBREEDING CLOSTERA ANACIIORETA. 

 BY C. G. BARRETT, F.E.S. 



Early in Jiiiiu two years ago Miss A. D. Edwards very kindly 

 sent me some eggs of Glostera anachoreta, mentioning at the same 

 time that the parent moths were descended from specimens of her 

 own capture several years before at Deal, also that the breed showed 

 symptoms of exhaustion, the last brood having been difficult to rear. 

 At first I found no symptoms of weakness ; most of the eggs hatched 

 and the larvje were thoroughly healthy, being blessed with appetites 

 of a most satisfactory nature. They took to Lombardy poplar and 

 fed up upon it in about a month, producing a fine brood of moths in 

 July, from which ])lenty of eggs were obtained. Some of these egga 

 were infertile, but a sufficient number hatched, and the larviB fed 

 most eagerly upon black or spreading poplar, so that about the end 

 of August 1 had an abundance of pupoe, and also had turned out 

 many larvae to shift for themselves among the abundant poplar trees 

 around. From the pupae reserved moths very soon commenced to 

 emerge and went on till all had appeared, forming a complete and 

 abundant third brood of moths in the season. These also paired 

 freely, and laid plenty of eggs, of which perhaps one-half were in- 

 fertile. The young larvae from the remainder were soon feeding on 

 both kinds of poplar, but there was no indication to be seen upon the 

 trees of any larvae out of doors. As the weather became cooler the 

 indoor larvae became more and more sluggish, feeding so slowly that 

 when the night fogs commenced a large portion of them were still 

 feeding. Then trouble began. The night fogs appeared to have even 

 more influence than the frosts in shrivelling the poplar leaves and 

 rendering them both worthless and distasteful to larvae, and it was only 

 by searching the neighbourhood for sound leaves in sheltered spots 

 that it was possible to induce them to feed up. By the commence- 

 ment of November, however, most of them had done so, and the rest 

 were necessarily thrown away. The pupae from these should, 

 according to rule, have laid safely through the winter to produce the 

 spring brood of moths. But early in November, in the shelter and 

 warmth of the house, the moths again began to emerge — a fourth 

 generation in the season— and in spite of all that I could do speci- 

 mens continued to make their appearance, day by day, till the middle 

 of December, when discouraged by being put out of doors into the 

 coldest part of the garden, and by frosts, emergence ceased. These 

 winter specimens were utterly inert, some of them could not spread 



