30 
Lake, while the Department of Agriculture where the writer's experi- 
ments were made, is situated in the city of Washington, only about 40 
feet above the Potomac. 
Three experiments were conducted with a view to the determination 
of the rate of development of this species in dried beans, as follows : 
April 30, twenty beetles were placed in a jar of disinfected dried 
beans, from which two adults issued June 18, or in 49 days (7 weeks). 
The following day, June 19, a second experiment began with the con- 
fining of adult beetles with other beans. From this lot three imagos 
of the new brood developed July 16, or in 27 days. 
The last experiment was undertaken in warm weather, and will denote 
approximately the minimum period of development in dried seed. 
Twenty imagos were placed with fresh beans June 19, and the first 
individuals issuing from these appeared July 10, or in 21 days (3 weeks). 
We thus have ascertained definite periods in the life history of this 
insect under different atmospheric conditions, showing a variation of 
from 21 to 80 days. 
It should be added that an experiment begun during an exception- 
ally heated period and conducted in a very hot room failed with this 
species, evidently on account of the excessive dryness of the seeds, 
although these had been partially decorticated for the purpose; also 
that the writer has evidence that the entire period from the laying of 
the egg to the issuance of the adult may be prolonged to three months 
or more in a sufficiently cold exposure. 
Eggs that were laid April 30 hatched May 8, or in 8 days. Eggs 
laid October 27 hatched November 13, or in 17 days. Weather unsea- 
sonably warm; temperature of room, 60° to 70°. 
The pupal stage in hot weather occupied 5 days, from July 16 to 21. 
From experience with other allied species I do not believe that 8 days 
represents the minimum egg period. In the same weather and under 
the same conditions the egg and pupal periods for most Coleoptera that 
have come under my observation are nearly identical. Thus we have a 
minimum life cycle of 21 days, as follows^ Egg, about 5 days ; larval 
period, 11 days; pupal period, 5 days. This would give, with Mr. 
Slingerland's results, the following variations according to the atmos- 
pheric conditions, heat and cold, and possibly dryness and moisture: 
Egg stage, 5 to 20 days; larval stage, 11 to 42 days; pupal stage, 
5 to 18 days ; entire life cycle, 21 to 80 days. 
A LITTLE-KNOWN GRAIN WEEVIL. 
(Caulophilus latinasus Say.) 
Prominent among the insects collected at the Atlanta Exposition is a 
little cossonine weevil, iu distinguishable from Caulophilus latinasus Say, 
found living in Indian corn and "Spanish peas" or chick-peas (Cicer 
arietinum) from Mexico. It was the only insect found in these par- 
ticular exhibits of seeds, and its work appears to be not entirely unlike 
