664 
Journal of Agricultural Research 
Vol. XXX, No. 7 
The extent of this work has varied in 
different years. In some seasons 5 to 6 
bushels of gipsy-moth eggs have been 
collected, and one winter about 9 
bushels were gathered. The greatest 
number of eggs handled at the labora¬ 
tory in one season amounted to more 
than 98,000,000 in the winter of 
1918-19. On an average, about 10 per 
cent of these were parasitized. 
For the first few years after Ana- 
status became established, most of the 
gipsy-moth egg clusters were collected 
near the centers of the few colonies 
which had been liberated. The eggs 
were so kept as to allow the non- 
parasitized gipsy-moth eggs to hatch, 
and the remaining material was divided 
for colonization in the spring. 
- TOM/ 30£/A/&*Je/£S ■ 0£//TjML 00£.0//y-C0£0///Z£0-/S09 
- /2040S <c±C0L0/vy C0Z0/V/2 r ££>-/£/0 
C >- 30 ire/ewjys 3//0 S0///& +*c0/.0#y colo/v/zz#-/*// 
. -70£S-Z00£T 0# Afae£///0# □ C0l0/yy C0A0/y/££0-/f/£ 
- r - S3Z4Af£i£ • C0£0//y 00£0S//Z£0-/0/S 
Fig. 8. —Chart showing area at Peabody, Mass., where some of the records of dispersion and percentage 
of parasitism by Anastatus were obtained. The checks on the eight lines are 100 yards apart and show 
the points where the sample collections of gipsy-moth eggs were made. The different marks on the chart 
show the location of Anastatus colonies liberated in this area during the different years. Scale, 1 inch= 
1.7 miles 
LATER LABORATORY METHODS 
USED IN HANDLING GIPSY-MOTH 
EGGS TO OBTAIN ANASTATUS BI- 
FASCIATUS FOR COLONIZATION 
Each fall small samples of gipsy- 
moth eggs from different locations are 
collected and examined to determine 
the percentage of parasitism by Ana¬ 
status. To obtain Anastatus for coloni¬ 
zation, large collections of egg masses 
are then made at the points where the 
parasitism is 10 per cent or more. 
The collections of egg masses in¬ 
creased from year to year until as 
many as 9 bushels of gipsy-moth egg 
clusters were collected and handled in 
one season at the laboratory. The 
methods used to separate the eggs con¬ 
taining parasites from the rest of the 
material have varied considerably and 
have been gradually improved until 
at present much of the work is prac¬ 
tically mechanical. These improve¬ 
ments have resulted in a large saving 
of time and expense. 
