648 
Journal of Agricultural Research 
Vol. XXX, No. 7 
male Schedius were in the presence of 
gipsy-moth eggs for 23 days, the re¬ 
sulting progeny showed that oviposi- 
tion had taken place during each one 
of these days. The females were then 
transferred to another lot of gipsv- 
moth eggs and continued to oviposit 
during the following three weeks. One 
individual oviposited 27 days later, or 
71 days after issuing. The other 
Schedius oviposited during a period of 
six weeks. Seventy per cent of the 
oviposition took place during the first 
three weeks of adult life. 
In regard to the later life of Schedius 
within the host egg, the following is 
taken verbatim from Bureau of En¬ 
tomology Bulletin 91 (p. 180), by L. O. 
Howard and W. F. Fiske: 5 
When the egg hatches, the larva does not entirely 
leave the shell, but remains with its anal end thrust 
into it, and the stalk, which is hollow, becomes 
functional and acts like a lifeline attached to a sub¬ 
marine diver in supplying a connection with the 
outer air. As the larva grows the stalk increases in 
thickness, and the last anal segment of the larva 
becomes covered with a thick chitinized shield, 
which is unaffected by the action of strong caustic 
potash. There are two larval molts, and conse¬ 
quently three larval stages. During the entire 
course of both the first and second the young para¬ 
site remains quite firmly attached to its anal shield 
and lifeline and the cast skins are not entirely 
sloughed off, but are merely pushed backward. 
After the third ecdysis it retains this connection for a 
while, and grows rapidly, but about the time when 
it reaches maturity the connection with the shield 
is broken, thus proving that it is not part and 
parcel of the integument. It would appear rather 
that this shield, including a tube within the egg- 
stalk (which, as stated, grows in thickness after the 
egg itself hatches), is actually part of the integu¬ 
ment of the first-stage larva, and that the second 
and third stages merely continue to use what is in 
effect the skin of the first larval molt. 
A third-stage larva, with egg-stalk 
and anal shield still retained, is shown 
in Figure 1, c, the detached egg-stalk 
and anal shield at d , and larval man¬ 
dibles at e. 
The Schedius larva within the gipsy- 
moth egg consumes the entire embryo 
if it is in a new egg in which the host 
larva has not developed. When the 
Schedius egg is placed within a host 
egg in which the gipsy-moth larva has 
developed, the parasite maggot devours 
the entire caterpillar except the hard 
chitinized parts and the hair. The 
hair is left clinging to the inside of the 
host eggshell. This superficial char¬ 
acter is used in determining that 
Schedius has been present in the egg 
under consideration. 
In 16 to 17 days after the deposition 
of the parasite egg the Schedius larva 
is full grown and transforms to its 
pupa (fig. 1, /). The usual period dur¬ 
ing warm weather from oviposition to 
the issuance of the adult parasite 
(fig. 2, d) is 21 days. This time varies 
considerably with the climatic condi¬ 
tions. More time is required for its 
development during prolonged cool or 
wet weather and late in the fall. The 
first spring generation requires about 
six weeks for development. 
FEEDING 
In the breeding work at the labora¬ 
tory adults of Schedius have been fed 
sugar sprinkled lightly on the inside of 
banana peeling. A solution of one- 
half honey and one-half water is also 
very satisfactory. This solution is 
placed on paper or blotting paper. 
(White blotting paper is used, since it 
was found that Schedius had sometimes 
died after feeding on this mixture 
placed on colored blotting paper.) 
Adult Schedius have been noticed ap¬ 
parently feeding at the punctures 
made by their ovipositors in gipsy- 
moth eggs. 
LONGEVITY EXPERIMENTS 
Schedius adults are quite hardy and 
live for many weeks when they have 
food and proper conditions. Records 
have been obtained of female Schedius 
living 24 days without food. The male 
Schedius do not live as long as the 
females and usually both sexes die 
within three or four days after issuing 
if food is not available. The longest 
records of adult life of Schedius with 
food are 105 days for males and 130 
days for females. Many records have 
been obtained of Schedius adults living 
for five and six weeks. 
NUMBER OF PROGENY AND PROPORTION 
OF SEXES 
Laboratory experiments to deter¬ 
mine the number of progeny from a 
single female Schedius have shown 
great variations. Many females die 
before they have had sufficient time to 
deposit the full number of eggs of which 
they are capable. This early mortality 
of many females under laboratory con¬ 
ditions is probably greater than occurs 
in the field. In laboratory experiments 
there probably is more superparasitism 
of the host eggs than is the case in the 
field. When more than one Schedius 
egg is placed in a gipsy-moth egg it is 
usually wasted, for very rarely does 
more than one Schedius develop in 
such an egg. 
Howard, L. O., and Fiske, W. F. the importation into the united states of the parasites 
OF THE GIPSY MOTH AND THE BROWN-TAIL MOTH: A REPORT OF PROGRESS, WITH SOME CONSIDERATION 
of previous and concurrent efforts of this kind. U. S. Dept. Agr., Bur. Ent. Bui. 91: 312, illus. 
1911. 
