64 Proceedings of the Royal Society of Victoria. 



After that comes the genus Phascolarctos, our little native 

 bears or koalas. I have kept numerous specimens of this animal 

 (P. cinereus) on his native gum trees, with nothing artificial about 

 him save a strap and rope whereby he could be pulled down from 

 time to time to have his temperature observed. Thus I made 

 eighty-three observations, the average of which amounts to 36 - 4°. 

 Females at the breeding time are always very decidedly above 

 the ordinary degree of warmth. If such cases be excluded, the 

 average is exactly 36°. But the average for males alone is only 

 35"2°. The range of variation may be seen in the following nine 

 observations taken at intervals upon the same female : — 



The range is here seen to be not very wide, yet I have often 

 known healthy specimens that had been for a while in the sun 

 stand as high as 37 "9°, while on a cool day or in a very shady 

 place the same individuals would be only 35 '3°, a range greater 

 than we would find under the same circumstances in any of the 

 higher mammals. The highest register I ever obtained for a 

 thoroughly healthy koala was 38-4°, which is a degree and a half 

 above the normal temperature of man; the lowest was 34 '9°, or 

 nearly two degrees below man's normal. The former temperature 

 would in man imply some constitutional derangement, a distinct 

 case of feverishness ; in the koala it denotes only that it has been 

 out in the sun. The lower temperature, though common in the 

 koala, is never met with in man except in rare pathological 

 conditions. It is below the range of our ordinary clinical 

 thermometers. 



I found that a big male specimen of this species, kept in a cool 

 shady place and registering 34-9°, could, by being brought into a 

 bright sun, be raised a tenth of a degree for every five minutes 

 he was kept in it. I regret that when I had abundant opportu- 

 nities I did not determine how far this warming process would 

 go ; but I have seen it continue for more than two hours at a 

 time. 



