THE OPEN SEA 79 
Greenland or “right” whale, right from the 
whaler’s point of view. 
The whale is fish-like in shape; it has fore- 
fins like a fish, and it swims by means of its 
powerful fish-like tail. Yet, though we talk 
of whale “ fishery,” we all know that a whale 
is not a fish but a mammal, that is, a warm- 
blooded animal that breathes by lungs, and 
gives suck to its young. Naturalists have been 
able to show, from a study of the whale’s own 
body and the bodies of its fossil relatives, that 
the ancestors of the whale were land mammals, 
and that, in taking to the sea, they lost many 
of the old characters of their race and acquired 
others more suited to their new mode of life. 
The body is now fish-like because that is 
the shape most suitable for cleaving the water ; 
the fore-limbs are flippers or paddles, yet 
within them “the whole inherited but greatly 
shortened skeleton of the mammalian forearm 
lies concealed.” The hind-limbs were no 
longer of use, so they disappeared, but traces 
of their bones can still be found hidden be- 
neath the blubber; the skin has lost its hair, 
except for a few very sensitive vibrisse or 
whiskers about the mouth, but indications of 
hair can be seen in the developing young; and 
