WHALES 125 



have a black skin, very short hair, four toes in front, three behind, 

 provided with broad hoofs. They are peaceful vegetable feeders, with 

 the snout prolonged into a short proboscis. 



ORDER XI. : WHALES (CETACEA). 



HAIRLESS, fish-like mammals, living in water. Hind-limbs absent, 

 fore-limbs fin-like. Tail fin horizontal. 



The Greenland Whale (Baltena mysticetus). 



A. Distribution. 



The Greenland whale is an inhabitant of the most northern parts 

 of the Atlantic and Pacific Oceans. It is among mammals what the fish 

 is among the vertebrates, an animal restricted to an aquatic existence. 

 This fact explains 



B. Its Structure and Mode of Life. 



1. This species and a few others of the same genus are the largest 

 mammals of the present and of pre-existing times. It attains to a length 

 of 68 feet, in some exceptional cases even 80 feet, and a weight of from 

 220,000 to 330,000 pounds (i.e., equal to that of 150 to 200 strong oxen). 

 An animal of such gigantic proportions could only live in water, and, 

 moreover, in the sea. Let us inquire why. In most land mammals the 

 body is supported on the two pairs of limbs, like a bridge on its pillars. 

 To prevent the bridge from collapsing, its pillars must be strong, and its 

 arches firm and rigid. If, however, the bridge is laid on the water 

 (e.g., a boat-bridge), it does not require so great a strength and solidity, 

 since it is supported on the water at all points. From this comparison 

 we may understand the strength of the larger land animals and the 

 immense size of the whale, a size which is vastly beyond that of all land 

 animals. (Compare also the size and firmness of aquatic plants.) 



2. The whale dives down into the depths of the sea, more particularly 

 when hunted (see below) or pursued. The pressure of water prevailing 

 in these depths must be stupendous, as will appear from the following 

 experiment : Discs of cork were attached to harpoons, which were thrown 

 into the back of a whale and carried with him down into the depths ; 

 when the animal was dead, these discs were found to have been compressed 

 to one half their former size. It seems at first sight incomprehensible 

 how the animal can bear this immense pressure. It becomes, however, 

 to some extent intelligible when we consider that most of the bones of 

 the body remain cartilaginous at their points of union, that the two 



