8 



BULLETIN 93, XT. S. DEPARTMENT OF AGRICULTURE, 



was then removed for a flight and put back the same evening, vi^here 

 it remained until March 28. From March 7 at 9 a. m. until March 

 28 at 4 p. m. readings were made on this colony every 15 minutes 

 night and day, with the exception of the period between 9 a. m. 

 and 7 p. m. on the 24th, when it was out of doors. During this 

 period of three weeks the temperature of the room was changed' 

 slowly, being raised as high as 64° F. and cooled to 13° F. 



Fig. 2. — Average daily temperatures of the center of the cluster of bees In colonies 1 

 and 3 and room temperatures, Oct. 14, 3 912, to Mar. 6, 1913. Taken from readings made 

 hourly from 9 a. m. to 4 p. m. The room temperatures are indicated by the heavy line. 



When this colony was first placed in the room for the regular 

 series of readings, after a preliminary confinement, October 12 (the 

 readings were begun Monday, Oct. 14) , it maintained a cluster tem- 

 perature which usually lay between 64° and 68° F., the da,ily average 

 temperature departing from these rather narrow limits only four times 

 up to November 22. The average temperature is 66.5° F. During the 

 first five weeks the temperature of the room was less regular than 

 later (due to faulty working of the regulating apparatus), and this 

 doubtless accounts for some irregularities in the cluster temperature. 

 At first the three thermometers in the cluster (1, 2, and 5) gave tern- 



