GRAPEVINE ROOT WORM 65 



days. The insects which made these records were confined in 

 jelly tumblers, with a small piece of cane and fresh leaves 

 supplied daily. A large number of beetles were also confined 

 in one breeding jar and fed in the same way as the isolated 

 pairs. A careful record of all eggs taken from this large breed- 

 ing jar was kept and the approximate average for each female 

 was 109. This latter indicates a strong probability of the 

 beetles producing many more eggs under natural conditions. 

 It is manifest that the above were not ideal conditions, and we 

 know that individual adults have an extended existence, some 

 in our breeding cages living and depositing eggs over most of 

 the period from July 3 to Aug. 19. This, in connection with 

 others being taken in vineyards as late as Sep. 5, renders it 

 very probable that females in the field deposit as many eggs, 

 if not a great many more. ^ 



Our observations on eggs laid in breeding jars showed that 

 they are deposited in masses of from 1 to 125, the latter being 

 the largest number observed in one cluster. A normal egg mass 

 measures about } inch in length and less than one half that 

 in breadth. The somewhat concentric arrangement of the eggs 

 is shown on plate 1, figure 3. The rows of eggs often over- 

 lap each other like shingles, and in the center of the mass there 

 is frequently an appearance of two or three layers. The egg 

 clusters are sometimes deposited so that two thirds of the 

 branch is encircled, and in each case the whole mass is covered 

 with a sticky substance, which glues each egg to the other in 

 such a manner that the whole may be easily detached from the 

 vine, as is often the case when a strong wind is blowing. 



The duration of the egg stage was determined by repeated 

 observations as from 9 to 12 days (it is stated to be eight days- 

 by Professor Webster), about one day being required for an 

 entire mass of eggs to develop after hatching commenced. We 

 were also able to verify Professor Webster's observation on the 

 appearance of a narrow semitransparent band or line near each 

 end of the eggs four days after oviposition. Small numbers of 

 empty egg shells, indicating that hatching had begun, were 



