GRAPE INSECTS 441 



appear in the vineyards about the time grapes are in blossom 

 and feed on the upper surface of the leaves for nearly a month 

 before beginning to lay their eggs. In feeding the beetles eat 

 only the upper epidermis of the leaf and leave characteristic 

 feeding marks about .,^7 of an inch wide and an eighth of an 

 inch long, which soon turn whitish and give a sure indication 

 of the curculio's presen(*e in a vineyard. 



In West Virginia egg-laying begins about the middle of June, 

 when the grapes are about one half grown, and continues till 

 they are ripe. The female first inserts her snout through the 

 skin of the grape and eats out a cavity under the skin ; then 

 turning around she places a small, white, elliptical egg on the 

 farther side of the cavity by means of her extensile ovipositor ; 

 and then seals the opening of the cavity with a drop of excre- 

 ment. The egg cavity shows on the surface of the grape as 

 a circular brownish spot with the puncture a little to one side 

 of the center. The female may continue to lay eggs for two 

 or three months, laying in all from 60 to nearly 400 eggs. 



The eggs hatch in five to seven days, depending on the tem- 

 perature, and the young grub tunnels through the fruit and 

 usually devours one or more of the seeds. The berry often 

 turns purplish around the egg puncture and usually drops 

 from the vine before the grub reaches maturity, thus leaving 

 the clusters thin and scraggled and greatly reducing the value 

 of the crop. The grub becomes full-grown in about twelve 

 days and then leaves the grapes through a small hole in the 

 skin. It is white with a brownish head, legless, and at the time 

 of leaving the grape is about f of an inch in length. Pupation 

 takes place in a small dirt-covered cocoon on or just below the 

 surface of the ground or under the protection of a stone or 

 piece of bark lying on the ground. The beetles emerge in 

 about 19 days. 



In West Virginia beetles of the new brood begin to appear in 

 the latter part of July and continue to emerge until the close of 



