300 THE CANADIAN ENTOMOLOGIST. 



Brunswick, Me., at light, and H. Argent eomaculatus, which is stated to 

 be pretty generally distributed, though it is certainly not common in the 

 imago state.* 



Now, if the females in this genus produce over two thousand eggs 

 each, it can be easily understood why they are so abundant in Europe, 

 but why are they so rare on this continent ? 



Mr. D. S. Kellicott, who discovered the larva and pupa of H. Argen- 

 teomaailatus, found that that species bored in the roots of Alnus incana, 

 but came up into the stem when mature, and Prof. J. B. Smith stated that 

 it bred also in oak, willow and poplar. Mr. Kellicott stated in his paper 

 upon this subject, which he read before this club at the Cleveland meeting, 

 that after these nearly mature larvae had come up into the stem, large 

 numbers of them were destroyed by woodpeckers. 



Upon reading this, it occurred to me that possibly this furnished the 

 key to the mystery of the scarcity of these moths on this continent, and I 

 therefore wrote to an ornithological acquaintance to ask if woodpeckers 

 were more abundant on this continent than in the Old World. This 

 gentleman replied that while he had no definite knowledge upon that 

 question, he should judge that we had in Canada ten to twenty times as 

 many woodpeckers to the square mile as they had in England. 



I must, however, confess that even if this estimate be correct it is not 

 an entirely satisfactory explanation, as there are on this continent a num- 

 ber of small species in this genus which no doubt feed in the roots of 

 shrubs or herbaceous plants where woodpeckers would not be likely to 

 find them, which are quite as rare as the larger species. I also wrote to 

 Dr. Strecker to learn whether, so far as he knew, Thule had ever been 

 found in any other locality than Montreal, to which he replied as 

 follows : — " Some years since, an example of Hepialus TJude was taken 

 somewhere in Wisconsin, I don't recollect where or by whom, but a 

 sketch was sent me at the time for identification, which I immediately 

 recognized as that species." 



In regard to the life-history of the species in this genus, the English 

 entomologists to whose works I have access are extremely vague. Stain- 

 ton, in his Manual I., 109, says of the genus, " Larva feeding on the 

 roots of plants," which leaves it very indefinite as to whether he means in 

 the roots or tunneling in the earth and feeding on the roots. He even 

 says that the larva of H. Hectus feeds on the leaves of dandelion, and F. 

 O. Morris says " on the dandelion." Newman, " British Moths," does 

 not commit himself as to Hectus, but of most of the others he says " on 

 roots," but of H. Velleda he says ; 'in thesubterraneous rhizome of the 

 common brake, (Pteris aquilina)? 



In spite of the very loose statements of English entomologists, I think 

 there can be no doubt that the larvae of this genus are internal feeders, as 

 stated by both Harris and Packard. 



*Since writing this paper Prof. J. B. Smith has called my attention to the fact 

 that H. McGlashani is very abundant. See Ent. Amer., II., 15. 



