Vol, 7, 1921 ZOOLOGY: BENEDICT, FOX AND BAKER 
155 
The natural inquisitiveness and restlessness of the elephants made the task 
of recording the skin temperature somewhat trying, although in no sense 
hazardous. The rhinoceros presented an unexpectedly favorable oppor- 
tunity for measurement, while the uncertain temperament of the hippo- 
potamus interfered greatly with the securing of records of his tempera- 
ture. An especially advantageous feature of this series of observations 
is the fact that the temperature of the environmental air in the elephant 
house at the New York Zoological Park remains relatively constant at 
about 19.5° Centigrade, night and day. 
Excluding records obtained at partially protected points, such as the 
back of the ear, the groin, and axilla, we found with a female Indian ele- 
phant a range in skin temperature from a minimum of 20.8° C. at a po- 
sition on the forehead, midway between the two eyes, to a maximum of 
29.6° C. on the shoulder. With a male African elephant the range was 
from 21.4° to 28.3° C. The relation between surface temperature and the 
distribution of the blood was strikingly evident in the temperature records 
on the ear, on the back side of which the veins are very readily observable. 
Near the veins the skin temperature was high. Owing to the cracks and 
crevices in the thick elephant skin, difficulty was at times encountered 
in securing records of surface temperature, especially on the sides of the 
body, since the tendency was for the warm air to rise, with a distinct 
circulation of air through the cracks in the skin. Every attempt was 
made to use as smooth a piece of skin as possible for the temperature 
measurements. The elephant, therefore, exposed to an environmental 
temperature of approximately 19.5° C, had a skin temperature which 
averaged not far from 25.5° C. While there were rather large differences 
at times between the two elephants, the general picture showed a reason- 
ably uniform bilateral temperature distribution. 
The rectal temperature of elephants has not been frequently reported. 
Dr. W. R. Blair of the New York Zoological Society found in his measure- 
ments that the rectal temperature of the elephant ranged from 97.2° F. 
(36.2° C.) to 98° F. (36.7° C). Using a clinical thermometer, we secured 
the rectal temperature of the male elephant and found it to be 35.9° C. 
On two occasions the thermometer was thrust quickly into freshly passed 
feces, and temperature records secured of 36.2° and 36.7° C, respectively, 
the large mass of feces losing heat slowly. Thus the elephant apparently 
has a rectal temperature slightly lower than the average commonly as- 
sumed for man. 
The skin of the rhinoceros is much smoother than that of the elephant, 
making possible much more satisfactory measurements. This animal 
was studied almost exclusively on one side of the body and gave temperature 
measurements ranging from 24.1° to 27.9° C. In general the tempera- 
tures were somewhat warmer in the lower part of the body. An approxi- 
mate average of 26.2° C. can be taken as the general skin temperature of 
