798 PERIODIC FUNCTIONS IN MAMMALS 



-4- 



■III — r 'I 



1 1 //»./ 



Fig. 5. Thirty-two-day record of running activity of a female chipmunk. 

 First and last periods in constant dim light (0.5 ft-c). Duration of period 

 of constant darkness in middle of record shown by vertical heavy line. 

 The record has been repeated (double width) to show the activity pattern 

 passing the limit of the initial 24-hr span. Otherwise coordinates as in 

 Fig. 1. 



mined, and from these values a temperature coefficient (^lo) for the 

 rhythm was calculated. For seven cases in which the body temperature 

 was depressed 6° to 17°C, the Qw values ranged from about 1.1 to 

 1.4. In three cases the body temperature was maintained at 37 °C 

 under anesthesia. In two of the cases there was no delay in the onset 

 of activity, while the delay shown by the third case was probably 



