654 
Journal o f Agricultural Research 
Vol. XXX, No. 7 
are stocked at intervals of several days, 
so timed that after the resulting genera¬ 
tions begin to issue the flow will be 
gradual and continuous; for it would 
be difficult to handle so many adult 
Schedius should they all appear at the 
same time. After the trays are stocked 
they continue to yield Schedius for four 
or five generations without further care 
except to feed the adults and to keep 
the room warm. In from 21 to 25 days 
after the introduction of Schedius into 
the breeding trays a new generation of 
parasites issues. 
In order-to draw the adult Schedius 
from the breeding trays it is necessary 
to exclude the light, which is done by 
placing pieces of black paper over the 
glass in the tops. The cork stoppers are 
removed from the front of the trays and 
glass vials (4 inches by 1 inch) are sub¬ 
stituted. The vials are held in place 
by means of small paper cones inserted 
in each hole. Electric lights are hung 
in front of the trays (fig. 3, a). As the 
Schedius enter the vials each vial is re¬ 
placed by an empty one and an estimate 
is made of the Schedius in the vial with¬ 
drawn. The adult Schedius are then 
transferred from the vial into a mailing 
tube 8 by 3 inches in size. To do 
this, in the top of the mailing tube is 
placed a removable cover with a trap¬ 
door through which the open end of the 
glass vial containing the Schedius is in¬ 
serted (fig. 3, d). By tapping the bot¬ 
tom of the inverted vial the Schedius 
drop into the mailing tube. When the 
glass vial is withdrawn the door springs 
back into place, preventing the Schedius, 
which are very active, from escaping. 
When the tube contains about 4,000 
Schedius a slip of paper smeared with 
a solution of one-half honey and one- 
half water is placed in it. The mailing 
tube is then covered with a piece of cot¬ 
ton cloth held in place by an elastic 
band. The colony is now ready for 
liberation and each day’s output is sent 
by mail or otherwise to men in the field. 
COLONIZATION OF SCHEDIUS 
The first colonization of Schedius in 
New England was made in the fall of 
1909. Colonies were liberated in five 
different towns. About 1,000 adults 
which issued from Japanese eggs were 
colonized. The others liberated were 
bred through a series of generations at 
the laboratory. In the spring of 1910 
large numbers were liberated in 89 
different towns. This colonization ma¬ 
terial was obtained from the stock used 
in the fall of 1909. Each year since 
1910 Schedius has been colonized 
farther out from Melrose, Mass., with 
stock obtained in New England, until 
at present over 20,500,000 Schedius 
have been liberated and 358 towns in 
New England have been colonized. 
Three towns in Maine have been 
colonized, 95 in New Hampshire, 203 
in Massachusetts, 31 in Rhode Island, 
and 26 in Connecticut. New Jersey 
has received nearly half a million 
Schedius, Washington, D. C., about 
20,000, and Illinois 17,000. The Sche¬ 
dius were sent to the last two places 
in order to test their ability to attack 
the eggs of the tussock moth, which 
were abundant at the time of liber¬ 
ation. A few Schedius have been 
sent to Maxwell, N. Mex., in connec¬ 
tion with the investigation of the range 
caterpillar (Hemileuca oliviae). About 
200,000 specimens were sent to Madrid, 
Spain, in the fall of 1923, where they 
are being bred for liberation in a heavy 
gipsy-moth infestation in the Royal 
Forest near Madrid. Schedius kuvanae 
is not present in Europe, and this para¬ 
site, if successfully introduced, should 
develop into an important enemy of the 
gipsy moth in Spain. It is likely to 
prove more effective in Spain than in 
New England, because the summer 
season in Madrid is longer, allowing for 
more generations of Schedius to develop 
and the winters are less severe than in 
the United States. 
The area which has been colonized in 
New England is shown in Figure 4. 
Table I gives the colonization rec¬ 
ords in a much abbreviated form. 
The colonization of Schedius is 
carried on during the fall, beginning 
about the middle of September and 
continuing into November, until the 
weather gets too cold for insect ac¬ 
tivity. As the colonies are prepared 
at the laboratory for liberation they 
are sent to men in the field for libera¬ 
tion or taken directly to the field for 
colonization. The colonies are placed 
from 1 to 2 miles apart where woodland 
and gipsy-moth infestations warrant it. 
Each tube contains 4,000 Schedius for 
liberation in suitable places in the 
area to be colonized. If the day is 
warm the Schedius are active and it is 
only necessary to remove the cloth top 
from the tube, when a few gentle taps 
will empty the tube of the parasites. 
The men liberating Schedius are sup¬ 
plied with a blue-print map, similar to 
that shown in Figure 11, indicating the 
roads in the town. The exact location 
of each colony is recorded on the map. 
In addition, a note is written giving 
the details of the colony site, so that 
the place may be visited at any later 
occasion. A roadside tree is marked 
with white paint with the letter “S” 
and an arrow pointing to the colony. 
