. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 14 BULLETIN im, IT. S. DEPARTMENT OF AGEICULTUEE the rest. Dorsal area of each armed with a pair of large spines and a pair of smaller ones. Lateral area of each tergite bearing a spine, at base of which is a small seta. Epipleural lobes each obscurely armed with two minute set«. Ninth segment armed as usual with two prominent pleural spines. LIFE HISTORY AND HABITS The granary weevil normally hibernates during the winter in either the adult or the larval form. The adult is resistant to low teniperatures and will survi
. Bulletin of the Department of Agriculture. Agriculture; Agriculture. 14 BULLETIN im, IT. S. DEPARTMENT OF AGEICULTUEE the rest. Dorsal area of each armed with a pair of large spines and a pair of smaller ones. Lateral area of each tergite bearing a spine, at base of which is a small seta. Epipleural lobes each obscurely armed with two minute set«. Ninth segment armed as usual with two prominent pleural spines. LIFE HISTORY AND HABITS The granary weevil normally hibernates during the winter in either the adult or the larval form. The adult is resistant to low teniperatures and will survive a very cold winter. Adults resume activity with the first warm weather of spring, and egg laying soon begins. Overwintering larvae at that time begin pupating. Hiber- nating adults kept in the laboratory at Washington, D. C, resumed egg laying in the early part of March. THE ADULT After transformation from the pupal to the adult form, the weevil remains within the seed for a short time until the body integuments harden and the color has changed to a dark chestnut brown. Some weevils remain to feed for a considerable time within the larger seeds. Shortly after emergence copulation takes place and is repeated at frequent intervals throughout the life of the weevil. The weevils are rather sluggish in their actions and are very easily handled. If disturbed in any way they draw their legs up close to the body and remain motionless for some time. The females may be distin- guished from the males by their smoother and more slender beaks. PARTHENOGENESIS „ ^ o „, ., ^ , , Virgin females of the granary weevil Fig. 8.—The granary weevil: Pupa, ventral , 9 , i , 1 • r view. Enlarged about 37 times have been oDserved to dcposit an oc- casional egg, but none of these DURATION OF ADULT LIFE WITHOUT FOOD The granary weevil is capable of surviving without food for a considerable period, much longer than the closely related rice weevil, possibly because of its less active
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