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 ami whether the larva has an abundance of suitable food. 

 July 14 and 16 w^ere the averages dates for males and females for the 

 year 1908. 



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



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

 in wliicli 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 tiates 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 wdll be noted that there is very little diil'.erence 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 ai)parent 

 than real, as the earth was very loose in 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 Ma}" 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 w^eek in June, beetles having been found on 

 or before June 4 (hiring the past three years. 



Mortality op 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 

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

 female beetles died. Of the young beetles 22 per cent of the males 

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

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

 die during the winter. 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 necessar}^ to conduct a number of 



