THE EFFECTS OF ATMOSPHERIC TEMPERATURE 

 UPON THE BODY TEMPERATURE OF MICE^ 



FRANCIS B. SUMNER 



THREE FIGURES 



1. INTRODUCTION 



In the course of some investigations, the results of which have 

 already been published in part,- certain effects of temperature 

 upon the length of the appendages of mice were found to reappear 

 in a succeeding generation, even though the latter was not sub- 

 jected to the experimental conditions. The author was well aware 

 that this phenomenon would be explained by many on the assump- 

 tion that the germ-cells had been directly influenced by the tem- 

 perature conditions to which the organism as a whole had been 

 subjected. To persons of this way of thinking the parallel modi- 

 fications of parent and offspring would thus be adequately 

 accounted for. 



In reply, it would be hardly sufficient to point out that mam- 

 mals in general are homothermous, and that the body temperature 

 of a mouse may therefore be regarded as invariable, whatever the 

 atmospheric temperature may happen to be. It has long been 

 known that even in the mammalia the atmospheric temperature 

 is not entirely without its effect upon that of the body. The nor- 



^ The investigations herein considered, together with others to be reported 

 upon later, were conducted at Woods Hole, Mass., during the winter of 1910-1911, 

 with the aid of two successive grants from the Bache Fund of the National 

 Academy of Sciences. Although these studies were completed nearly two years 

 ago, the writer has been prevented by other duties from preparing the results for 

 publication. There have now been added, in a supplementary note, the results 

 of certain other experiments performed since the paper was first prepared for 

 pubhcation. 



^ Journal of Experimental Zoology, August, 1909; American Naturalist, Janu- 

 ary, 1910;Archivfur Entwicklungsmechanik der Organismen, June, 1910; American 

 Naturalist, February, 1911. 



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