368 



ALBERT C. EYCLESHVMER. 



the above temperatures are too high for artificial incubation, it is 

 necessary to push the inquiry a step further with a view of 

 determining the exact temperature of the egg during natural 

 incubation. The temperature of the hen recorded below was 

 obtained from a thermometer attached to a block as described 

 above. The temperature of the egg was taken in the following 

 manner : A pail of lukewarm water was brought to a tempera- 

 ture of 98 F. (by the addition of warm or cold water). The 

 egg was then placed in a tightly fitted rubber bag and held about 

 four inches below the surface of the water. An opening was 

 then made in the shell directly over the embryo, and a self regis- 

 tering thermometer warmed to 98 inserted for five minutes. 

 The thermometer was inserted just far enough to bring its lower 

 end at the center of the egg. As often as the eggs were broken 

 for testing, they were replaced by eggs taken from other hens 

 set at the same time. 



A second series of readings was made by gently removing the 

 hen from the nest and placing the thermometer in the groin for 

 five minutes. The results are of course somewhat unsatisfactory 

 since again the excitement of the fowls, due to their being re- 

 moved from the nests, resulted in temperatures somewhat higher 

 than normal. 



While the above are the only sets of daily observations, they 

 were supplemented by a number of scattered tests. In no case 



