SEASONAL HISTOKY. 



33 



The summary of these records (Table VIII) shows that the female 

 beetles on an average, not individually, survived the males by 4 days. 



Table VIII. — Summary of the length of life of individual male and female beetles of 



Table VII. 



Sex. 



Average. 



Maximum. 



Minimum. 



Male 



36.4 



Days. 

 54 

 60 



Days. 

 1 

 21 







The maximum length of life for the males was 54 days, while that 

 for the females was 60 days. In Table V is given further a summary 

 of the length of life of the beetles in the stock jars, where no separate 

 record has been made as to life of male and female individuals. 



THE EGG. 



INCUBATION PERIOD OF THE EGG. 



The time necessary for the hatching of the eggs depends largely 

 upon the prevailing temperature and probably also upon moisture 

 conditions. Experiments to test the effective limits of these influ- 

 ences have not been made, but the results of these factors have been 

 in a general way well marked as is evident from the difference in the 

 time of hatching of individual Qgg clusters throughout the season 

 (see Table IX). In different sections of vineyards the hatching 

 probably varies slightly, since some eggs are located in well shaded 

 places, while others are so situated as to receive more heat from the 

 sunlight. In the middle of the hatching period eggs which were kept 

 in an open outdoor shelter hatched, on an average, in 12 days. The 

 rate for hatching for the entire egg period is shown in Table IX. 

 51282°— Bull. 89—10 3 



