4 MISC. PUBLICATION 188, U.S. DEPT. OF AGRICULTURE 
HYPERPARASITISM 
The parasite cocoons or puparia which developed after the arrival of 
their hosts at the laboratory were never exposed to the secondary 
parasites which would normally attack them in that stage, and any 
species of secondaries reared from them must have attacked the pri- 
mary parasite while within its host and prior to the time of collection. 
It is evident that the numbers of these would never approximate the 
natural hyperparasitization in the field, so although many species of 
secondaries were reared they have not been included in the present 
list. 
METHODS OF HANDLING MATERIAL 
It has been customary to supply the regular collectors with mailing 
tubes and note slips. The data requested with each collection have 
been as follows: State, town, date of collection, name of collector, 
food plant, abundance, degree of defoliation, approximate area 
infested, and any other data of interest. 
On receipt at the laboratory the larvae were counted, identified if 
possible, and placed in suitable containers for rearing. Since most of 
the material is received in the larval stage it is important to identify 
the insects in that stage, especially when a solitary larva or a collec- 
tion containing only a few individuals is received, since parasitization 
or death from other causes would prevent determination were this 
deferred until the adult stage was reached. / 
Usually, when a species was received for the first time, one or 
two representative larvae were inflated or placed in a preserving solu- 
tion for future reference. The inflation of larvae, especially of the 
macrolepidoptera, has proven most satisfactory for the purposes of 
this investigation. The several hundred inflated larvae now in the 
laboratory collection are invaluable in the identification of such species 
as appear in abundance only at long intervals, and of solitary larvae 
which never seem to be found commonly. 
The type of cage used depended upon the number of larvae and 
whether or not they required soil for pupation. Larvae not requiring © 
soil were placed in wooden trays with cloth bottom and glass top, 
pasteboard boxes, small tin cans, or glass jars. Those that required 
soil were placed in glass-covered metal trays with at least a part of 
the bottom covered with fine-mesh wire, or in various types of glass 
jars and tin cans into which had been placed soil or peat moss to a 
depth depending somewhat upon the size of the container. Each 
collection of larvae necessarily had to be supplied with its proper food 
and given care throughout the larval instars, and then examined regu- 
larly for adult issuance. Late in the fall, after all possibility of adult 
issuance had passed, the containers with the hibernating material 
were stored in a cool place where temperature fluctuations were slight. 
In recent years a stall in a cement garage has been used for this pur- 
pose. The material had to be examined regularly for issuance during 
the spring, and a few species required examination throughout the 
entire summer. 
Adults of the Lepidoptera needed for identification or for the col- 
lection were killed as soon as they emerged and were spread while 
fresh. 
