THE TEMPERATURE OP THE BEE COLONY. 19 



rearing. Root (1908) calls attention to the necessity of maintaining 

 a temperature of not more than 45° F. (7.22° C.) at the approach of 

 spring. The writer is not aware that any systematic study of the 

 temperatures of bees in cellars has ever been made, so that it is 

 impossible to say how the temperature of the cluster would compare 

 with that of the colony under experimentation. The prevailing 

 outside temperature, however, in the present experiment was found 

 to be about 45° F. (7.22° C.) for several days previous to the laying 

 of the first eggs, March 9. 



At any rate in this experiment it appears that a temperature of 

 45° F. (7.22 C), with an occasional maximum outer temperature of 

 8° to 11° C, is closely associated with the beginning of egg laying. 

 But there are probably other factors of importance, particularly the 

 matter of food. In establishing the experimental colony late in the 

 fall, it was impossible for the bees to store any pollen. In the spring, 

 however, for a week previous to egg laying they were seen gathering it. 

 This might be expected to be an important stimulus to egg laying, 

 and the bees could not rear brood until some could be gathered. 

 While there appears to be a close relation between stimuli, tempera- 

 ture out of doors, and pollen gathering to the laying of eggs, details of 

 the phenomena can be worked out only on a larger number of colonies 

 under experimental conditions. 



Another noticeable phenomenon which occurred at this time was 

 the equalization of the temperature throughout the cluster. This 

 might occur earlier in colonies protected from the winds and in sunny 

 locations and later in colonies less favorably situated. If, however, 

 upon experimentation this should be found to be one of the funda- 

 mental stimuli to egg laying, it would in a measure explain the fact 

 that eggs do not always appear at the same time in all of the colonies 

 of a bee yard. Another factor would be the strength of the colony 

 and the resulting heat which it could produce and conserve. These 

 results of the present investigation suggest great possibilities for dis- 

 covering the stimuli which regulate the beginning of egg laying in the 

 spring and which might influence the periodicity of brood rearing 

 during the summer. 



So far the consideration has been largely of the period in which 

 eggs were laid and which preceded directly the beginning of incubation 

 or brood rearing. It will be seen, therefore, that this time is in a sense 

 transitional from the winter condition to the summer season, the 

 topic which will next be considered. 



TRANSITION FROM WINTER TO SUMMER CONDITIONS. 



The phenomena mentioned in the preceding caption which accom- 

 panied the laying of the first eggs marked the beginning of the transi- 

 tion from winter to summer conditions, but this transition was not 



