362 ADELE M. FIELDE. 



first callow appeared on January 29, 1905. This indicates about 

 twenty days for incubation, a month for the larval and twenty 

 days for the pupal period, all at a time when the congeners of 

 this queen were merged in winter repose. 



This N. queen shared the labors of the workers in the care of 

 the young, which continued to develop until the 26th of March, 

 when I removed the nest to a room having a fairly steady tem- 

 perature of 70 F. At this temperature the remaining cocoons 

 failed to hatch, and the fifty larvae ceased to grow. The larvae 

 did not increase in size till the last days of the following June, 

 after the temperature had risen to 76 F. The first cocoon of 

 this newer brood was spun August 6, 1905. 



Although this queen had deposited eggs in March, 1904, she 

 deposited none in March, 1905, nor did she lay any thereafter 

 until July 26, 1905, when she again deposited a few eggs. 

 During the first week in August, 1905, the eggs were increased 

 to about the same number that she had laid at the same season 

 two years previously. Her failure to lay eggs in August, 1904, 

 was doubtless due to the agitation consequent upon her service 

 in several of my experiments at about that time. I have often 

 observed that psychic influences affect the deposit of eggs by ant 

 queens. Her failure to lay eggs in March, 1905, was probably 

 due to exhaustion consequent upon the work to which she had 

 been stimulated by high temperature in the previous December. 



Since the food supply, the humidity, and the number of workers 

 were factors whose variation was but slight in the nest of this 

 queen, it appears probable that the time of the development of 

 eggs and the growth of the young was determined mainly by the 

 temperature. 



EXPERIMENT B. 



My Creuiastogastcr lincolata queen laid hundreds of eggs in 

 August, 1904, and the larvae therefrom grew scarcely at all until, 

 on November 20, 1904, I removed her nest from a room where 

 the usual temperature had been 70 F. to a chamber where the 

 temperature was usually from 82 to 85 F. Early in Decem- 

 ber the larvae began to increase in size and on December 22 the 

 first pupa appeared among them. The young continued to thrive 

 and fifty-three pupae had been developed in the nest before March 



