A STUDY IN HYPERPARASITISM Pash 
as determined by observations upon specimens which were carried 
through their development in glass cells. The period from the depo- 
sition of the egg to the emergence of the adult from the host cocoon 
was found to range from 17 to 34 days, the length of this period being 
largely dependent on the temperature. After an egg stage of 2 to 5 
days, from 5 to 8 days were required for the feeding period, and the rest 
of the time spent in the cocoon was passed as resting fifth-stage larvae 
and as pupae. In the case of specimens that were held under constant 
observation none of the larval instars, except the last, covered more 
than 24 hours. After the cessation of feeding the larva remains 
quietly in the last stage from 6 to 14 days before transforming to 
a pupa, and the pupal period covers 5 to 12 days. 
There are several generations annually, as many as five being pro- 
duced at the laboratory under outdoor temperatures. It was noted 
that cocoons attacked prior to September 1 usually produced adults 
of the hyperparasite the same season, whereas those attacked after 
that date normally carried the full-grown hibernating larva over the 
winter. : 
Its reproductive capacity, its gregarious habit, and its characteristic 
of passing through several generations a season combine to make this 
species a hyperparasite of exceptional importance. 
COELOPISTHIA SCUTELLATA MUESEBECK (27) 
In the experience of the writers this species has not been of major 
importance as a parasite of Apanteles melanoscelus, but its general 
similarity in biology to the closely related Dibrachys boucheanus 
suggests that it may, under the proper conditions, become a serious 
enemy of this Apanteles. 
Like Dibrachys, it is a gregarious ectoparasite on the Apanteles 
larva or pupa, and the eggs and larvae of the two hyperparasites 
are practically indistinguishable. About 25 to 30 days are required 
for development from egg to adult, except in the hibernating gen- 
eration, while the actual feeding period of the larva covers only 
7 to 9 days. There are from one to three generations annually, there 
being considerable irregularity in this, as has been noted with most 
multiple-brooded hyperparasitic species; and hibernation occurs 
in the form of full-grown larvae. The adults of the hibernating gen- 
eration appear in early June. Like most of the hyperparasites 
discussed, this species also produces males in parthenogenesis. 
HABROCYTUS DUX GIRAULT 
Urbahns (37) has discussed, in some detail, the life history and 
habits of Habrocytus medicaginis Gahan as a primary parasite of the 
alfalfa-seed chalcis, Bruchophagus funebris Howard; and Pierce, Cush- 
man, Hood, and Hunter (31), and Wellhouse (88) have recorded spe- 
cies of this genus as primary parasites of weevil larvae. In general, 
however, the species of Habrocytus are probably hyperparasitic; 
attacking various braconid and ichneumonid cocoons. Although 
not obtained in great abundance, most of the collections of Apanteles 
melanoscelus cocoons have produced Habrocytus dur in some num- 
bers. It must be included among the more important parasites 
of that primary. 
