elt HAIR OF WHALES 341 
dimensions of the bigger Whales are probably due to the fact that 
measurements have been taken, not in a straight line from snout 
to tail, but along the bulging sides of the Cetacean, rendered even 
more convex than in nature by decomposition, and by pressure 
due to the immense tonnage of the creature. 
The Cetacea are the most perfectly aquatic of all mammals ; 
they never leave the waters which they inhabit. It is true that 
legends have represented them as pasturing upon the shore— 
Aelian spoke of Dolphins basking in the sun’s rays upon the 
sand; and the “Devil Fish” of California, Rhachianectes (see 
p- 357) has given rise to improbable stories —but they are 
Fie. 180.—Killer. Orca gladiator. x 3, (After True.) 
apparently only legends. Indeed a stranded Whale cannot 
live long, for it is unable to breathe, the comparatively feeble 
breast being crushed by its own weight. In accordance with 
the purely aquatic habit, we find a modification of the outward 
form of the body (and as we shall see later of many of the in- 
ternal organs), which renders the Cetacea externally unlike all 
other mammals. The form is fish-like, the fore-limbs are paddles, 
the tail is expanded into two horizontal flukes, which serve to 
propel the creature through the water. 
The skin is smooth and shiny, so smooth and so shiny that it 
has often been compared to coach leather. But nevertheless 
they are not entirely without that most essential character of the 
class Mammalia, a coating of hair. The hairy covering is, how- 
ever, reduced to the very smallest proportions; it is represented 
