46 Dr Davy on the Temperature of Man and other Animals . 
even amongst different members of the same family ? The si- 
milarity of temperature in different races of men is the more 
remarkable, since between several of them, whose temperatures 
agreed, there was nothing in common but the air they breathed, 
— some feeding on animal food almost entirely, as the Vaida,— 
others chiefly on vegetable diet, as the priests of Boddho, — 
and others, as Europeans and Africans, on neither exclusively, 
but on a mixture of both. 
Farther, That the temperature of birds, of all animals, is the 
highest,— that of the mammalia next, — that of the amphibia, 
fishes, and certain insects, next in degree, — and, lowest of all, 
that of the mollusca, Crustacea, and worms, — are conclusions, 
with few exceptions, that may be deduced from the preceding 
experiments on the temperature of animals in general. 
Moreover, since in general, as far as experiment and obser- 
vation have yet gone, there appears to be a decided connection 
between the quantity of oxygen consumed by an animal and 
the animal’s heat, is there not good reason to consider the two 
in the relation of cause and effect ? 
If animal heat be owing to nervous energy, or any way con- 
nected with the nervous system, why, it may be asked, are birds 
so much hotter than the mammalia ? Why is the temperature 
of most quadrupeds higher than that of man ? 
Or, if it be owing to digestion, and secretion, and animal ac- 
tion, why is the temperature of the amphibia and of fishes so 
low, whose powers, in respect to these functions, are so consi- 
derable ? 
Or, if it be connected with muscular energy, why are the 
animals whose muscular powers are most remarkable (the ani- 
mals belonging to all the lower classes), equally remarkable for 
the lowness of their temperature ? 
Or, lastly, if animal heat at all depend on peculiarities of 
structure and organization, why, it may be asked, is not the 
temperature of the amphibia elevated like that of birds, — the 
structure of the respiratory, and digestive, and secreting organs 
of the one class being so much alike those of the other ? 
