14 
It passes the winter either as adult (fig. 3) or within the dead and 
dried swollen body of its host (fig. 6), but with the coming of spring 
and a temperature of about 60° F. during the day the adults appear 
in the fields. They do not affect the “ green bug” alone, but some 
other aphides as well, and are therefore present whether this pest is in 
the fields or not. 
The female goes about, if in grain fields, among the plants, and 
when she finds an aphis she quickly throws her abdomen underneath 
her body and between her legs and with a spring-lhke motion thrusts 
her ovipositor into the body of the aphis, leaving therein a tiny egg. 
This egg hatches into a larva in a few 
days, and the usual position in the body 
of the “ green bug” of the larva up to the 
time it becomes full grown is shown in 
fig. 4, page +. Up to this time it has 
fed within the body of the “ green bug ” 
without reaching any of the vital parts, 
but preventing to a greater or less degree 
the giving of birth to young. This is an 
important fact, for, as the parasite seems 
to prefer partly grown young, it begins 
to check the increase of the pest before 
the death of the * green bug” takes ‘place. 
Mr. Phillips has found that females par- 
asitized at this period of their development 
do not reproduce more than a very few 
FIG. 6.—Dead ‘‘green bugs,’”’show- (|g ys, After about six davs the parasite 
ing hole from which the matured ~ 5 ; a z 
parasite of Iasiphiebus tric: larva gets its full growth and begims ta 
emerges.) The top figure shows: work its way about within the sulllivims 
the lidstill attached, but pushed aes . A = 
back; the bottom figure shows ody of its host. At this stage, however, 
the parasite emerging. Enlarged it beoins to be more active and works itself 
(original). 
about all through the abdomen of its host, 
which now dies a seemingly terrible death. The motions of the para- 
sitic larva within cause the skin of the * green bug ~ to become rotund 
in shape, as shown in fig. 6; the skin also becomes darker and hardens. 
Within four days (the life cycle in warm weather occupying about 
ten days) the adult Lysiphlebus emerges through a tiny round hole 
in the dried skin of the “ green bug,” as shown also in fig. 6. In 
fields that have been destroyed the leaves become almost covered by 
their brown bodies, as shown in fig. 5. As stated, many of the 
“oreen bugs” are stung by the Lysiphlebus while quite young, and 
if these develop to winged adults, as they at times do in myriads and 
[Cir. 93] 
