1943] 
Bionomics of Ectopsocus pumilis 
55 
mating position. On other occasions they approached each 
other and bumped head-on several times and furiously rubbed 
their heads together; then the male tried to approach the female 
from the side. The female raised the anterior part of her body 
and the male backed under with his wings erect. The female 
was directly above the male, but when the genitalia were united 
she side-stepped and the male’s wings dropped back and rested 
across hers. They remained perfectly motionless, except for 
an occasional twitch of the palpi or antennae, for twenty-two 
minutes. Usually the male started to walk first and when he 
stopped the female started. This brought them almost to a 180° 
angle, facing in opposite directions. Each tried to go its way, 
with the result that the male usually dragged the female a short 
distance. Then they separated. A few minutes later the male 
approached as before, then stood still and appeared to rapidly 
raise his abdomen and head and rock forward and backward. 
It was not possible to determine if the tip of the abdomen or 
labium touched the substratum during these rapid motions. The 
male again approached the female and, failing to regain the 
mating position, went through these movements again. The 
genitalia of the male remained exposed for some time after 
mating (Fig. 13). 
Copulation apparently did not occur within twenty-four hours 
after both sexes had moulted to the adult. Eggs deposited by 
females exposed to males for that period only did not hatch. In 
several instances adult males were observed trying to copulate 
with nymphs in the sixth instar. 
Oviposition. — Eggs were found in the field in the fall and 
late spring on the inside of the corn sheaths (Fig. 8). They 
were most commonly found on the sheaths about four or five 
feet up on the stalk. The lower sheaths apparently fitted too 
tightly around the stalk, making it almost impossible for the 
cseciliids to crawl under the sheath. Near the top of the stalk 
the inner surface of the sheaths is exposed, offering little pro- 
tection from the weather; so eggs were seldom found there. In 
late fall the eggs were sometimes found on exposed ears espe- 
cially around kernels injured by the corn earworm. In late sum- 
mer eggs were found on the drying leaves (Fig. 9) in the tunnel 
formed by the midrib and especially around caked pollen. 
Eggs were laid in groups of one to sixteen, most commonly 
four to eight with an average of about six. The females seemed 
