GRAPEVINE ROOT WORM 17 



ance of the earliest insects and the laying of eggs ; and, if, as 

 can hardly be questioned, the insects remain without taking food 

 for two or three days, then the time of feeding before the deposi- 

 tion of eggs can hardly exceed an equal period. The first beetles 

 were observed in 1903 on June 19, and a few contained nearly 

 developed eggs July 2, at which time it was very warm and there 

 were many pairing, and eggs were deposited a day or two later, 

 making about two weeks between the appearance of the first 

 beetles and the deposition of eggs. This period is a little longer 

 than was the case in 1902, but even then does not equal our breed- 

 ing cage records. This matter is of considerable importance 

 because it shows how quickly collecting must be done or poisons 

 must act in order to prevent the deposition of many eggs. 



The feeding of the beetles occurs almost entirely on the upper 

 surface of the leaves and, as described by Professor Webster,. 

 " is done by gathering a quantity of the substance of the leaf in 

 the mandibles and jerking the head upwards, after which the 

 body is moved a step forward and another mouthful of food 

 secured as before. After securing a few mouthfuls in this way, 

 they move to another place and begin again, thus eating out 

 numerous chainlike rows of silk net " as shown on plates 5 and 

 6. '' The insects usually eat only to the lower epidermis on 

 foliage having a velvety undersurface, but on others they eat 

 entirely through the leaf." The beetles are shy and retiring by 

 nature and feed largely in sheltered places or among the grow- 

 ing tips, both difficult places to hit with a spray. A favorite 

 retreat of the insects is among the tendrils clinging to the top 

 wire. Many of those feeding on the leaves are easily frightened, 

 and when alarmed usually fold up their legs and fall to 

 the ground, where they remain quiet till all danger appears to 

 have passed. They can spring readily either with the legs or 

 when inverted by suddenly opening the wing covers and pro- 

 jecting themselves from the hand or other support. The beetles 

 on the canes, however, are not so easily disturbed. They can 

 frequently be picked from the vine, and it requires repeated 

 jarring to dislodge all. This is of considerable importance when 

 collecting beetles with any machine, and the persistence with 

 which some hang to the wood is an objection to this method of 



