INSECTS INJURIOUS TO THE GRAPE 



467 



Life History. The beetles hibernate over winter in or near 

 the vineyards, especially along the edge of woodlands. They 

 appear in the spring about the time the grapes blossom and feed 

 upon the foliage for three or four weeks until the berries are 



FIG. 389. The grape curculio (Craponius incequalis Say): a, beetle; 6, head 

 of same from side; d, larva from above; e, same from below; /, pupa 

 all much enlarged. (After Quaintance, U. S. Dept. Agr.) 



about one-fourth grown. The beetles cut small characteristic 

 holes in the leaves, and this habit of feeding on the foliage so 

 ^^^^^^^^^^^^3 long makes it possible to kill them with 

 arsenicals before oviposition is commenced. 

 In West Virginia the females begin egg- 

 laying late in June, most of the eggs being 

 laid in early July, but egg-laying may 

 continue for eighty-one days, during which 

 time a female will lay an average of 257 

 eggs. The female excavates a small cavity 

 in the berry in which the egg is placed and 

 hatches in four to six days. Infested berries 

 often show a purplish spot around the egg- 

 puncture. The larva bores in the pulp and 

 in three or four days reaches the seed, 

 which is then devoured. The larva becomes full grown in twelve 

 to fifteen days, when it eats its way out of the berry and drops 

 to the.ground in search of a suitable place to pupate. The mature 

 larva is white, about one-third inch long, tapering from the middle 

 of the body toward either end, without legs, and clothed with fine 

 short hairs. The larvae make small earthen cells under stones, 



FIG. 390. The grape cur- 

 culio in act of egg-lay 

 ing -natural size; e, 

 showing position of egg 

 in grape enlarged. 

 (After Brooks.) 



