- 4 - 
In the cages located at Lockhart only 8 beetles emerged prior to 
June 19. The rainfall on June 19-20 was 1.27 inches, and immediately after- 
ward the emergence increased. A total of 65 beetles emerged on June 22-24. 
From June 21 to July 9 inclusive' there were only two light showers in this 
section and the total rainfall was only 0.25 inch. On July 10 a rain of 
1.87 inches occurred. The emergence was only 21 beetles for the 3-day period 
July 9-11, but after the rain had softened the soil the emergence on July 
12-14 was 360 beetles, or 45.2 percent of the total emergence. Frequent 
examinations of the soil in this section from June 21 to July 12 showed 
that the numbers of full-grown larvae and pupae were decreasing and the 
number of adults increasing, but that owing to the lack of moisture the 
adults were remaining within the pupal cells and not attempting to cut 
their way out, 
Activitie s of the a dults . — After emerging, the adults crawl to the 
nearest plant or other object protruding from the soil and remain there 
for several hours to allow the body to harden. After the body has hardened, 
those resting on objects other than plants move in search of plant foliage. 
A portion of the beetles spend a large part of their preoviposition period 
without migrating any appreciable distance, provided they find favorite 
host plants, but many do migrate considerable distances during the pre- 
oviposition period. Immediately after emergence the adults are found in 
clusters. On cotton plants they congregate near the terminal buds but 
usually on the underside of the leaves. In peanuts the beetles are usually 
found on the lower part of the vines near the surface of the soil. Beetles 
emerging in cornfields that are not intercropped with velvetbeans or peanuts 
usually migrate therefrom in search of other food soon after emerging. 
The beetles confine their feeding to the outer margin of the leaves, usually 
the portion of leaf nearest the petiole. They prefer the older leaves of 
all plants rather than the tender buds. They feed frequently but consume no 
great quantity of leaf surface. On cotton plants 30 inches in height, where 
100 to 200 beetles fed for 6 to 10 days, less than 50 percent of the leaf 
surface was consumed. On velvetbeans 100 to 150 beetles have been observed 
to feed for several v/eeks without consuming more than 25 percent of the 
leaf surface. In a few instances where peanuts adjoined heavily infested 
cornfields the adjacent rows of peanuts have been totally stripped by the 
hordes of migrating beetles. 
After the beetles have passed the preoviposition period they leave 
the plants to deposit eggs. At the end of each day's activity they usually 
come to rest on the ground beneath plant foliage, in crevices in the soil, 
or on the lower portion of plants. Observations made at various hours during 
the day and night showed virtually no activity on dark nights. The period 
of greatest activity is from 1 p. m. to 4:30 p. m.; however, there is con- 
siderable movement between 9:30 a. m. and 6 p. m. In a well-ventilated 
insectary open to natural light conditions at all hours, beetles deposited 
62 percent of the total egg masses between 12 m. and 4:30 p. m. , 31.8 percent 
between 4:30 p. m. and 8 a. m., and only 6.2 percent between 8 a. m. and 
12 m. Although at certain periods most -of the adults are found on the under- 
side of the leaves, they are most active during the hours of most intense 
