26 



throughout the Hawaiian Islands, on the lowlands and well 

 up into the mountains. They are found common wherever 

 army worms or cutworms are numerous. In examination of 

 numerous army worms collected at different times from several 

 different districts, not so many were parasitized by this Tachina 

 as by Frontina arrhippirora, yet a good many were; and of the 

 rarer native cutworms which I have obtained s]3eciniens of 

 from time to time, more were parasitized by Chaetogaedia 

 than by Fronthia; in fact, it is difficult to get specimens of 

 some of the native cutworms which are not parasitized. Other 

 species of caterpillars are also parasitized by this Tachinid. I 

 have reared it from 11 different species of caterpillars. 



This fly is much larger than a house fiy, and of much the 

 appearance of the large grey flesh fly, from which, however, it 

 may be readily distinguished by its habits and flight. It is 

 more solitary, and does not frequent decomposing substances. 



The following observations on the habits of this fly were 

 ])ublished by the writer in the Proceedings of the Hawaiian 

 Entomological Society, II, ISTo. 1, pp. 7-9, Oct. 1908. [Paper 

 read at March meeting. 190S]. 



"It is but recently that I discovered the method of egg-laying 

 of this fly. It is usually stated in entomological literature that 

 Tachina flies lay their eggs on the bodies of their hosts; in fact 

 with certain species the act has been observed, but for far the 

 greater number of them the act of egg-laying has not been observ- 

 ed, or at any rate not recorded. That Chaetogaedia had a different 

 method of laying eggs was surmised, when in June. 1907 this 

 parasite was reared from more than half of a lot of pupae of 

 Agrotis cinctipennis, one of the less common native cutw-orms. The 

 eggs of this lot of cutworms were hatched in breeding cage and 

 grew to maturity without the possibility of access of a Tachina 

 fly; hence, considerable of a mystery arose when more Tachinids 

 than moths bred out from the lot. 



"This mystery was not cleared up till in February, 1908, when 

 in watching a female Chaetogaedia, as I supposed, hunting for cater- 

 pillars amongst grass and weeds, I observed that she was laying 

 eggs on the grass leaves. She would quickly crawl around among 

 the leaves, only stopping momentarily to place an egg here and 

 there on the surface of a leaf, never more than one per leaf. They 

 were placed on the leaves of weeds as well as on the grass. After 

 making this observation, it was easy to explain how the caterpillars 

 previously alluded to, became parasitized; for they were daily 

 supplied w^ith food (mostly Sonchus) gathered from outside where 

 Tachinas were common, and had undoubtedly deposited many eggs 

 on the leaves. The caterpillars ate the leaves with the eggs there- 



