50 



CALOSOMA SYCOPHANTA. 



hibernation in the pupal cavity. The date when young beetles go 

 into hibernation depends almost entirely on the time when the eggs 

 are laid and whether the larva has an abundance of suitable food. 

 July 14 and 16 were the averages dates for males and females for the 

 year 1908. 



Table IX. — Average date of emergence of Calosoma sycophanta from hibernation. 





Number of beetles. 



Age of 

 beetie; 



Average 



date 



males 



emerged 



from 

 hiber- 

 nation. 



Average 

 date 



Year. 



Males. 



Females. 



females 

 emerged 

 from 

 hiber- 

 nation. 



1908 6 



1909 { It 



^ { 2 g 



39 



17 



251 



16 



Old Jime i 



do Jime 8 



Young June 13 



do. . June 1 



Old Jime 6 



June 3 

 June 10 

 June 13 

 June 3 

 June 7 



The date of emergence depends on the weather and on the location 

 in which the beetles spend the hibernating period. 



During the spring of 1909 the weather was very cool in May and 

 in early June, and as a consequence the average dates of greatest 

 emergence extended from June 8 to 13, while the following year the 

 average extended from the 1st to the 7th of June. 



From the table above, which contains the records of 734 specimens, 

 it will be noted that there is very little difference in the date of 

 emergence of males and females. A greater discrepancy is shown 

 between the old and young beetles, but this is probably more apparent 

 than real, as the earth was very loose hi some of the cages, so that the 

 beetles hibernated very deep in the ground, and hence their emergence 

 was delayed. The earliest date of emergence is May 8 and the latest 

 June 29. 



In general it can be said that most of the emergence will take place 

 in the field during the first week in June, beetles having been found on 

 or before June 4 during the past three years. 



Mortality of Calosoma Beetles During Hibernation. 



During the winter of 1908-9, 35 per cent of the old male beetles 

 and 25 per cent of the old female beetles died, and the following 

 whiter 31 per cent of the old male beetles and 27 per cent of the old 

 female beetles died. Of the } T oung beetles 22 per cent of the males 

 and none of the females died during the winter of 1909-10. This 

 data would seem to indicate that about one-third of the old beetles 

 die during the whiter. The mortality of the young beetles in hiber- 

 nation on the average is probably less than 20 per cent. 



These results were secured from beetles that hibernated under 

 favorable conditions. It was iiecessarv to conduct a number of 



