APANTELES MELANOSCELUS GIPSY-MOTH PARASITE. 11 
generation maggot about two hours to form' its cocoon and the sum- 
mer maggot three to four hours to complete the cocoon in which it 
is to hibernate. 
The cocoon made by the spring-generation maggot is pale yellow- 
ish white, a little smaller and rather delicate as compared with the 
hibernating cocoon, which is a light sulphur yellow and very tough. 
LOCATION OF COCOONS. 
The cocoons of the spring generation are found singly or in 
clusters, depending upon the degree of gipsy moth infestation and 
the abundance of Apanteles. In low growth the cocoons are very apt 
to be found on the foliage and often on the debris on the ground, 
as well as along the trunk and small branches. On large trees a few 
cocoons are found on the foliage, but if abundant the majority are 
located at the junction of the smaller brandies on the underside. 
The cocoons are attached lightly, often on top of others and in- 
variably a dead second-stage gipsy moth larva is found with each 
cocoon (PL II, B, C, D). After the adults have issued these cocoons 
are easily washed or blown from the trees and are seldom found the 
next spring. 
The second-generation cocoons are found securely attached scat- 
teringly over the tree trunk and in clusters under the larger limbs 
where the gipsy-moth larvae congregate. These cocoons are not 
often found on the foliage. 
The gipsy-moth larvae, when parasitized by the second generation 
of Apanteles melanoscelus, have a tendency to crawl to protected 
and out-of-the-way places just before the issuance of the parasite 
maggots. The cocoons are often associated with the gipsy-moth 
pupae and larger caterpillars. They are found behind billboards 
and signs, attached to trees (PL III, 9 D), on the undersides of 
boards on the ground (PL II, A), under fence rails or rocks, under 
loose bark, and on rough surfaces on the underside of limbs (PL 
III, B, C). Plate III, A, shows a tin vessel found during the sum- 
mer of 1920 in a dump at Weymouth, Mass., and illustrates the 
habit of parasitized larvae of crawling to hidden places. There are 
a few over 100 cocoons on the bottom of this vessel, and there is a 
cluster of 25 cocoons on one side of the vessel not shown in the 
photograph. 
SEASONAL HISTORY. { 
The seasonal history varies considerably with the season. The is- 
suance of adults of Apanteles melanoscelus from their hibernating 
cocoons begins about the time of maximum hatch of the gipsy-moth 
eggs, which is usually near the middle of the second week in May. 
During such a season most of the Apanteles will have issued by May 
20. Under field conditions females of Apanteles melanoscelus do not 
