Temperatures of Reptiles, etc. 63 



This is an immense range for a mammal, and suggests a 

 reptilian want of capacity for temperature regulation. Moreover, 

 though the concomitancy between the air and the body tempera- 

 tures is by no means strict, there is enough to show that the one 

 in a large measure follows the other. It is to be remembered 

 that while a monotreme may rise and fall with the air, yet the one 

 change will follow the other after a dehnite period of time, and 

 an hour after sunset, though the air in a box may have grown 

 much cooler, the echidme in that box may have only begun to 

 cool. 



The temperatures given by Dr. Richard Semon in the recent 

 number of his important work, Forschungsreisen in Austmlien, 

 run as follows : — 



Here also the generally low temperature, combined with the 

 wide range, even though it is not strictly concomitant with 

 changes in air-temperatures, seems to suggest affinities with rep- 

 tiles. 



The next stage in the anatomical classification brings us into 

 the order of the marsupials, and here again we make an upward 

 step in view of a temperature higher, but not so high as that of 

 mammals in general ; steadier, but not so steady as is usual in all 

 the remaining orders. I have observed the temperatures of 

 sixteen different species of marsupials, and they average 36° 

 exactly, as the result of 126 observations. They are thus 3° 

 below the average of other mammals. 



The marsupial whose temperature, so far as I have observed, 

 comes next above the monotremes is the wombat, which stands 

 at 34-1°, as the average of single observations made on two speci- 

 mens (Phascolomys lasiorhinus, 3 4 -3°, and P. platyrhinus, 34°). 

 Next seems to stand the genus Petaurus, or flying squirrel. Mr. 

 Ernest Le Souef was good enough to observe for me the tempera- 

 tures of five specimens in the Zoological Gardens of Melbourne. 

 The average is 35 -7 °. 



