WHALES AND THEIR NEIGHBORS. 239 



air which is entangled or mechanically suspended in the water. At- 

 mospheric air containing the vitalizing oxygen for the renewal and 

 purification of the blood is the great desideratum on the part of all 

 animals, high and low alike. And the gill and lung, therefore, differ 

 simply in the manner and method in which the blood in each is 

 brought in contact with the air, and not in the essential details of their 

 work. The whales are known to " blow," and the act of " blowing " 

 is simply the act of breathing to be more particularly noticed here- 

 after. Thus, a whale or seal would be drowned as certainly as an 

 ordinary quadruped would be asphyxiated, were its periodical access 

 to the atmosphere prevented ; and the curious fact may here be men- 

 tioned that there are also certain abnormal living fishes notably the 

 climbing perch and qphiocephali of India which, to use the words of 

 a writer, are as easily drowned as dogs when denied access to the air. 

 There is little need to particularize any of the remaining characters 

 which demonstrate the whale's relationship to mammals, and its differ- 

 ence in structural points from the fishes. The young whale is thus 

 not merely born alive, but is nourished by means of the milk-secretion 

 of the parent, and this last evidence of direct connection with higher 

 animals might of itself be deemed a crucial test of the place and rank 

 of the whales in the animal series. 



But, granting that in the whales we meet with true quadrupeds, it 

 may be well to indicate the chief points in which they differ from their 

 mammalian brethren at large. It may be admitted, at the outset, that 

 they present us with a very distinct modification of the quadruped 

 type. Their adaptation to a water-life is so complete, in truth, that it 

 has destroyed to a large extent the outward and visible signs of their 

 relationship with mammals. The body is thoroughly fish-like and 

 tapers toward the tail, where we meet with a tail-fin, which, however, 

 is set right across the body, and not vertically as in the fishes. This 

 latter difference, indeed, is a very prominent feature in whale-struc- 

 ture. The limbs, as already remarked, are represented by the two 

 fore-limbs alone. No trace of hinder-extremities is to be perceived 

 externally, and the anatomical investigation of the skeleton reveals at 

 the best the merest rudiments of haunch-bones and of hind-limbs in 

 certain whales, of which the well-known Greenland whale may be 

 cited as an example. A distinct character of the whales has been 

 found by naturalists of all periods in the " blowholes " or apertures 

 through which the whale is popularly supposed to " spout." Thus we 

 find on the upper surface of the head of a Greenland whale a couple 

 of these " blowholes," or " spiracles," as they are also called. These 

 apertures exist on the front of the snout in the sperm whales, while in 

 the porpoises, dolphins, and their neighbors the blowhole is single, of 

 crescentic shape, and placed on the top of the head. It requires but 

 little exercise of anatomical skill to identify the " blowholes |' of the 

 whales with the nostrils of other animals ; and it becomes an interest- 



