184 PARASITES OF GIPSY AND BROWN-TAIL MOTHS. 
In the course of the first unavoidable experiment in partheno- 
genesis the attempt was made to secure the fertilization of the female 
through union with her own asexually produced offspring, but, 
although she lived after they had completed their transformations, no 
results were secured. It seemed to be within the bounds of possi- 
bility that success would follow if the experiment were differently 
conducted, and accordingly in the fall of 1909 Mr. Smith repeated 
it, with this variation, that the females, after they had deposited a 
few eges, were rendered dormant by exposure to moderate cold, 
awaiting the issuance of their progeny. This time no difficulty was 
experienced. The parthenogenetically produced males mated freely 
with their respective parents, and the subsequent progeny in each 
of several instances consisted of both sexes. 
Females thus reared were mated with their brothers (which were 
at the same time their nephews), reproduced with the ordinary 
freedom, and their progeny were of both sexes in the usual proportions. 
Still another generation showed no signs of weakness or any sort of 
abnormality, and the experiment was discontinued. 
In sexual reproduction the males appear always to be largely out- 
numbered by the females. Nothing like the diversity in this respect 
which has been noted in the case of other chalcidids has been observed 
in the case of Schedius. 
REARING AND COLONIZATION. 
When the first individuals of Schedius were secured from the 
imported Japanese egg masses in April, 1909, there was no diificulty 
in securing reproduction upon gipsy-moth eggs collected in the open, 
but by the time the second generation was secured those which had 
remained in the open were about to hatch, and would hatch almost 
immediately they were brought indoors. <A large quantity of eggs 
had been placed in cold storage in anticipation of this, and it was 
found that these would hatch nearly as quickly when they were 
removed. Oviposition at any time within a few hours of the time 
when the eggs would otherwise hatch was generally successful, but 
when the eggs hatched within 36 hours after being exposed to the 
degree of warmth necessary to secure oviposition of the parasite, it 
soon became evident that not very much increase was to be expected. 
Accordingly, the experiment was made of killing the host eggs through 
exposure to just enough heat to bring this about. The parasites ovi- 
posited in these dead eggs with the same freedom that they would 
’ attack the living, and reproduction ensued. The progeny, however, 
were small and weak, and not as prolific as those secured earlier in 
the spring. 
Thus, in one way and another the species was carried through the 
summer, and with the deposition of fresh gipsy-moth eggs early in 
July much better results were secured, and the parasites immediately 
