87 



autumn on gipsy-moth es^gs, l)ut tailed to survive the rigorous 

 New England winter. 



The other egg-parasite of the Gipsy ]\Ioth (Aiiastafus) occurs 

 both in Europe and Japan. Many thousands of this parasite 

 were reared from imported material, and colonized in several 

 places. Later investigations of these colonies showed that the 

 parasites had established in most of them, and were dispersing 

 slowly, and that as high as 29 per cent, of gipsy-moth eggs were 

 parasited in some instances. This parasite only attacks the eggs 

 soon after they are deposited and before any embryonic develop- 

 ment has taken place. Its life cycle was found to be perfectly 

 correlated with that of the Gipsy Aloth. producing one genera- 

 tion per year the same as the moth. The first-mentioned egg- 

 parasite, however, produces several generations per year, and 

 they only attack the eggs after the young caterpillar has become 

 fully formed within the egg, living in and destroying this young 

 caterpillar before it hatches. That is, it is an internal parasite 

 of an unhatched caterpillar. It passes through one generation 

 per month, but apparently does not hibernate in gipsy-moth eg8:s, 

 and needs another host to carry it through the spring till the 

 gipsy-moth eggs are deposited in mid-summer. 



Of the parasites on caterpillars of the Gipsy moth, many have 

 been introduced, both Hymenopterous and Dipterous. Alost of 

 the Hymenopterous parasites were not considered important ; but 

 one Braconid (Apantelcs) gave great promise in the ease with 

 which its cocoons could be transported, being successsfully car- 

 ried from Japan in cold storage all the way. Many thousand 

 were received alive, and from the adults emerging from them 

 seveial colonies were established success lully. The adult of 

 this parasite deposits its eggs (often many) inside a living cater- 

 pillar. \\'hen the young parasites are full grown, they emerge 

 from the dead or dying caterpillar and spin their white silken 

 cocoons in the immediate vicinity. Although so successfully 

 established at first, yet the later reports are that this parasite can 

 no more be found. They have hopes, however, that it will soon 

 be found abundant ; that it may have become widely scattered 

 like some others that they have had, that seemed to be lost for 

 a time on account of being so widely scattered that none could 

 be found until they had increased greatly in numbers. 



This species afforded ODOortunity for extensive investigations 

 on hyperparasites. Thirty or more species of hvoerparasites 

 were reared from cocoons of this parasite imported from Japan. 

 In shipments of cocoons of the same parasite from Russia, 20 

 to 25 species of hyperparasites were reared. After colonies of 

 the parasite had become established, many of their cocoons were 

 collected and these found to be hignly parasitized. Eighteen 

 species of American hyperparasites were found to attack this 

 host, which has no doubt been a factor in its dispppearance. 

 (Conclusion next number.) 



