CHAPTER XIII 



Order VIIL Cctacca 



(Whales and Dolphins) 



UNDER the general name of Cetacea, i.e., the Whales, 

 are classed together a wonderful group of marine 

 Mammalia, which includes not only the true Whales, but 

 also the Dolphin, Narwhal, Porpoise, and Grampus. 



Notwithstanding their marked resemblance to fishes, the 

 Cetacea possess the most indubitable mammalian character- 

 istics. By means of lungs they breathe atmospheric air; 

 their warm blood is pulsated by a four-chambered heart; 

 and they produce living young, which in their youthful 

 stages derive nourishment from the milk that they draw 

 from their mothers. Usually there is only one young one 

 at a birth, Rorquals proving the exception in sometimes 

 having two offspring. 



Though the Cetacea vary in size and differ in many 

 details, they all agree in certain additional points. With 

 the exception of a West African species of Dolphin, which 

 is at least partly herbivorous, these marine mammals are 

 carnivorous. They possess no hind limbs, but use a hori- 

 zontal appendage to propel their bodies through the water ; 

 and this form of tail is particularly serviceable in assisting 

 the animal to rise quickly from a great depth to the surface. 

 The fore limbs are composed of four or five digits, which 

 are only visible in the skeleton. Many species possess a 

 dorsal fin. Underneath the skin is a thick layer of fat, 

 from eight to twenty inches in thickness, which is called 

 blubber. Whaling men speak of it as the ' blanket.' The 



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