8 BULLETIir 1085, U. S. DEPARTMENT OF AGRICULTURE. 



an average life cycle of 52 days. This is 18 days longer than the 

 shortest^ record obtained and considerably shorter than the life cycle 

 during me winter months. 



LONGEVITY. 



The average length of life of the adult weevil is about 152 days 

 when reared in captivity. Of fertihzed females one lived for 209 

 days while two unfertilized females lived for 240 and 244 days, 

 respectively. 



When deprived of food these weevils are capable of living for 

 extended periods if the temperature is not too high. Fifty weevils 

 were placed without food in a chamber with a constant temperature 

 of 60° F. The majority lived for a period of 55 days, while a few 

 survived for 90 days and one for 96 days. During normally warm 

 weather these weevils will live for from 5 to 12 days without food. 



PARASITES. 



The larvae of this weevil are attacked by three hymenopterous 

 parasites, Cercocephala elegans Westwood, Aplastomorplia vandinei 

 Tucker, and Zatropis sp. 



Larvse, pupge, and eggs are all attacked by a predacious mite, 

 Pediculoides ventricosus Newport. 



CONTROL MEASURES. 



This weevil may be effectively controlled by the standard remedies 

 advocated for the control of insect pests of stored grain. 



TECHNICAL DESCRIPTION OF IMMATURE STAGES. 



EGG. 



Egg opaque, shiny white, bottom broadly rounded, top flattened and fitting into a 

 translucent cap. Length, "without cap, 0.45 to 0.47 mm. ; width, 0.27 to 0.32 mm. 



Mature larva 2 to 2.5 mm. in length, a white, footless, fleshy grub, with body curved 

 and wrinkled. Head light brown or straw color, the anterior margin and mandibles a 

 darker brown. Head about as broad as long, almost circular in form. Epicranial 

 and frontal sutures distinct and light in color. There are also two oblique, longitu- 

 dinal, light stripes rising from the frontal sutures and coalescing with the epicranial 

 suture near the base of the head. Frons sub triangular, with a distinct dark median 

 Line running from posterior angle to middle, and indicating carina. Frons provided 

 with four pairs of large setae, sutural margins each bearing one seta. Epicranial lobes 

 bearing the following setse: One close to posterior angle of frons and located in the 

 oblique, longitudinal stripe rising from the frontal suture, one small seta posterior to 

 this and near occiput, two anterior to it on disk of epicranium, two opposite middle of 

 frons, one opposite middle of mandible, one opposite hypostomal angle of mandible 

 and one on hypostoma near base of mandible. Epistoma represented by thickened 

 anterior margin of the front. Pleurostoma represented by somewhat darker declivous 



