EGG PARASITES OF TTIE GTPSY MOTH. 
181 
Schedius is to all purposes, if not to all intents, a secondary para- 
site upon occasion. In the spring of 1909 a generation was carried 
through to maturity within the larvae 
of Anastatus, and at that time there 
w as no difficulty experienced in induc- 
ing the Schedius females to oviposit in 
such. In the course of later experi- 
ments which were designed to deter- 
mine whether there was any preference 
shown between the eggs containing 
healthy caterpillars and those with the 
larva* of Anastatus, only the healthy 
eggs were selected for oviposit ion by 
the parent females. What was more, 
although several later attempts were 
made to force Schedius to oviposit in 
eggs containing Anastatus larva 1 , none 
but the first w as successful. 
Oftentimes two or more eggs are 
deposited in one host. Numerous in- 
stances have been found in which second-stage 
Fig. 21.— Schtdius luvanx: Egg-stalk ami 
anal shield of larva as found in host 
eggs of gipsy moth from which the adult 
Schedius has emerged, or in which the 
Schedius larva has been attacked by a 
secondary parasite. Greatly enlarged. 
(Original.) 
larvae were feeding 
peaceably 
still more 
Bide 
have 
Fig. Zl.—ScfHrfiii* l:\nanst: 
Larval mandibles. Greatly 
enlarged. Original.) 
by side as the result of such superparasitism, and 
been observed in which the former presence of more 
than one individual was positively indicated 
by t lie presence of more than one egg-stalk 
and anal shield, but never, out of many 
thousands of examples under observation, 
has more than one adult parasite issued 
from one egg. What happens to the su- 
pernumerary individuals is not indicated 
further than that they disappear, and that 
their substance goes to nourish the sole survivor. Whether there 
is an actual struggle for supremacy in which victory comes to 
the strongest, or whether the struggle 
takes the form of a contest to deter- 
mine which shall quickest consume 
the available food supply, the loser 
calmly surrendering his body to the 
winner by way of forfeit, has never 
beei) revealed. 
The story of a triple tragedy is told in Plate XI, figure 3, w hich is 
drawn from a slide prepared by Mr. Smith. It represents a single 
gipsy-moth egg, which had been attacked by Anastatus before the 
embryonic caterpillar had developed sufficiently to leave percept ible 
Fig. 28. — TyniarichlU noise: Larval man- 
dibles. Greatly enlarged. (Original.) 
