60 
Psyche 
[Sept.-Dee. 
walked up the side of the glass to the cotton plug. Other species 
sometimes had to be coaxed for a long time before they would 
walk upon a piece of corn sheath. This habit made it easy to 
transfer cultures from an old cylinder to a freshly prepared 
one. This species was successfully reared both in colony and 
individual cultures as described by Sommerman (5). 
The adults exhibited somewhat regular periods of extreme 
activity. This was especially noticeable in cultures decidedly 
overcrowded (i.e., in comparison to any conditions normally 
found in the field). Late at night they became active but the 
cause is not known. They may have been stimulated by hunger, 
temperature, light from the desk lamp, or perhaps it was just 
a daily rhythm. 
Overwintering. — This species was numerous on corn plants 
only in the fall. The heaviest infestation encountered occurred 
at Lawrenceville, 111., in October 1938. In December 1939 it 
was numerous in a cornfield at Urbana, and was the common 
species found on corn at Mt. Carmel, Conn., during the same 
month. Eggs were not easy to find. Those taken in the field 
from December to April did not hatch when brought into the 
laboratory or when left out of doors. Usually eggs found during 
the winter were straw-colored and withered. Adults taken from 
the field December 30, 1939 at Mt. Carmel, Conn., deposited 
fertile eggs within two days after being brought in from out of 
doors. Living nymphs or adults were not taken in the field 
between January first and April first. An active male that had 
probably overwintered was found in the sheath on an uprooted 
corn stalk April 9, 1940. 
On December 12, 1939 some nymphs and adults of E. pumilis 
were put in a tube and left out of doors. February 6 they were 
transferred out of doors to a clean tube. On April 1 an adult 
male, female and three nymphs were still alive. The cotton 
plug in the tube was moistened and they all drank readily. By 
April 9 these individuals had become active and their bodies 
were plump. By April 16 the overwintering female had de- 
posited a mass of ten eggs. These eggs were taken into the 
laboratory for rearing, to see if the change from variable out- 
of-doors temperatures to the abnormal indoor temperature 
would interfere with hatching. Seven of the ten hatched and 
all the nymphs matured. On April 2 1 one of the overwintering 
nymphs moulted to an adult and the overwintering female had 
