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INTERNATIONAL CONGRESS OF VITICULTURE 



Since several eggs are often deposited in a single fruit, it is probable that 

 cannibalism is practiced by the older and stronger individuals. Most of the 

 larvae leave the fruit during the months of July and August; however, a 

 few continue to issue up to the last of September. 



Pupa. 



The Pupa. 



The pupa is a delicate, white form of the insect, which is intermediate 

 between the larval and adult stages. It occupies a globular-shaped cocoon 

 composed of grains of sand and earth held together by silk. The cocoon 

 may be formed under any convenient object lying on the ground or it may 



Pig. 5. Cocoons of grape curculio. 



be placed just beneath the surface of the soil or in an exposed position on 

 the ground. The insect remains in the cocoon undergoing transformation 

 anywhere from thirteen to twenty-three days, the greatest numbers emerg- 

 ing as beetles on the eighteenth and nineteenth days. 



The Adult. 



The adult grape curculio is a small, robust snout-beetle which measures, 

 exclusive of the snout, about one-tenth of an inch in length. When the beetle 

 first issues from the cocoon it is black with a grayish cast imparted by a 

 sparse covering of minute white hairs. Within a few days the black ground 

 color fades to dark brown. The beetles are inconspicuous and are not often 



