12 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION. 



inclined to think that few, if any, deposit more than three or possibly 

 four clusters, making a total of not to exceed one hundred, or possibly, 

 one hundred and twenty eggs. From fifty to seventy-five will be nearer 

 the average. The majority of the beetles in our cages laid but a single 

 cluster of twenty or twenty-five, but those were under slightly un- 

 natural conditions where there was not a constant supply of fresh food. 

 A number of females were dissected to determine the number of eggs 

 in the ovaries, and these varied from sixteen to twenty-four well 

 developed eggs. 



The eggs of a cluster are very slightly glued together with a sticky 

 material. By careful handling it is possible sometimes to take these off 

 en masse, but the majority of clusters will fall apart upon the slightest 

 handling. The eggs of the eastern species are said to be covered with 

 a gummy material which holds the entire mass securely together, but 



with this species we failed to 

 find any that would withstand 

 any very rough handling or 

 which could be blown off the 

 vine in clusters by the wind. 



Time Required to Hatch. In 

 our breeding cages the shortest 

 time required to hatch was eight 

 days, and the longest period 

 twelve days. This was under 

 conditions which varied but little 



FIG. 7. Larva of the California grape root- from that of the vineyard, the 



temperature being lower, if in 



any way different, especially in the forenoon, since the laboratory had 

 a west exposure away from the morning sun. A large number of eggs 

 were thus timed for the incubation period and they all came within 

 the limits stated above. This, of course, may vary in warmer or colder 

 weather, but from ten to twelve days may be taken as the average 

 hatching period. The eggs of the same cluster were all observed to 

 hatch within one day. 



The Larva. The young larva upon hatching from the egg makes 

 its way to the ground almost immediately. It may crawl to the 

 ground, as we infer from finding them pretty well scattered down 

 the trunk of the vine, or they may possibly in many cases simply drop 

 to the ground, though this was not actually observed. This seems to be 

 a common habit with the eastern species, but here in California with 

 the short-pruned vines, and consequent nearness to the ground, we 

 believe that most of the larva? crawl down the trunk. Young larva? 

 kept under observation in a test tube filled with compacted soil, wan- 



