THE COWPEA WEEVIL. 87 
In a heated period the beetles may be so active as to gnaw their 
way out from the holes in the seed within 24 hours. The males seek 
the other sex almost as soon as they emerge from the seed and copula- 
tion and egg laying begin very soon thereafter. Copulation has been 
witnessed within at most four hours after issuance, and eggs have 
been found the same day. 
LIFE-CYCLE PERIODS. 
This species was kept breeding throughout the winter in a warm 
room with an average temperature of about. 70° F. During March 
and April experiments on the life cycle were begun. A number of 
adult weevils were confined in a rearing jar with fresh beans April 27, 
and removed after 24 hours, numbers of eggs having been laid dur- 
ing that period. From this lot larvae began to emerge from the eggs 
May 5, showing a period of incubation of 8 days or about the same as 
for (Bruchus) Acanthoscelides obtectus in about the same tempera- 
ture, which has been ascertained to be between 8 and 10 days. 
A larva, about to transform to pupa on April 9, pupated on April 
10, and appeared as imago April 20, or in 10 days, in similar cool 
weather in April. Five larvee were removed from their cocoons in 
the beans and assumed the pupal state April 20, from which two 
issued as imago April 27, or in 7 days in slightly warmer weather. 
The remainder failed to transform, and it was noticed that about 25 
per cent of the larv, removed from their cocoons when about to 
transform to pup, perished before assuming the adult condition, 
showing the necessity of the protection of the cocoon within the seed. 
A pair of weevils was confined in a rearing jar May 23, with chick- 
peas, and from this lot the next generation was obtained June 24, or 
in 32 days. 
Tn another lot of chickpeas, which were still drier than the last, the 
imago did not develop until 38 days, showing that this species natur- 
ally develops in fresh seed more rapidly than in dry seed. In garden 
peas, beetles developed in 30 days, from June 7 to July 7, in still 
warmer weather. In other lots kept under different conditions in a 
cooler room, the entire life cycle in March and April was 45 and 60 
days in two experiments. 
Another experiment was made in a hot room during the latter part 
of June and in July and the entire life cycle was passed in 21 days, 
from egg to adult, showing with the next experiment that in the 
warmest season of the year in a climate like that of the District of 
Columbia, where the temperature not infrequently reaches from 90° 
to 100° F. for prolonged periods, this insect may pass through its 
transformations in an astonishingly short time. 
Finally a lot of fresh beans was placed in a rearing jar containing 
beetles June 23, and in a few days the beans were removed covered 
