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unfitted for procuring its vegetable diet^ and unable to retain 
within its mouth the medusae which might enter that organ. 
Surely the fate of such a creature would be gradual starva- 
tion. How is it then, we ask, that we have any whales at all 
at the present day ? How ! In this way answers a living 
naturalist :* — In Horth America the black bear was seen by 
Hearne swimming for hours with widely open mouth, thus 
catching, almost like a whale, insects in the water We 
do not question this fact : but we do question the conclusion 
drawn from the fact. The philosopher goes on to say, Even 
in so extreme a case as this, if the supply of insects were 
constant, and if better-adapted competitors did not exist in 
the country, I see no difficulty in a race of bears being 
rendered by natural selection more and more aquatic in their 
structure and habits, with larger and larger mouths, till a 
creature was produced as monstrous as a whale.^^ This is one 
of the monstrous things which, on the hypothesis of evolution, 
we are asked to believe ! But we prefer, however, to let 
reason control our imagination, and accept its verdict that 
such a faith as this is inconsistent with common sense. There 
is another fact in connexion with the structure of the whale 
which should receive special attention. The whale, as an 
aquatic air-breathing mammal, cannot exist without a constant 
oxygenating of its blood. And yet the creature can remain 
submerged for an hour, and not suffer any inconvenience. 
And this it can do by reason of a special provision which has 
been made to supply the system with a constant flow of 
arterial blood during the period of its submergence. And 
this is how it is effected. While the heart of a whale is not 
larger in proportion to the size of the creature than is the 
heart of any other mammal, the quantity of blood contained 
in the body is much greater ; and there are special arteries 
and veins provided to hold the extra quantity of the circulating 
fluid. 
When the whale comes to the surface of the water to 
breathe, the aerated blood does not all pass to the heart, 
and from hence to the system, as in other mammals, but some 
of it passes to a reservoir provided for it — which reservoir 
consists of a number of arteries situated at the back of the 
chest. When the creature plunges beneath the water to 
obtain its food, or to evade its enemies, the store of pure blood 
is propelled through the system, and, after being used, is 
passed into another reservoir of veins, where it is stored up 
* Origin of SjJecieSf C. Darwin, first edition. 
