WHAT,E-BONE WHALES. 259 



consumes other Mammals, such as Seals and its own kindred. 

 Hunting their prey either near the surface of the water, oi at a 

 greater or lesser depth below, Whales are obliged to come up 

 at stated intervals to breathe, when they renovate the air in 

 their lungs by the well-known action of "spouting." 



Roaming at will through the trackless ocean, most Ceta- 

 ceans apparently conform but little to laws of geographical dis- 

 tribution; a large number of species being more or less cosmo- 

 politan in their distribution. Certain species, such as the 

 Greenland Whale, the White Whale, and the Narwhal, are how- 

 ever, more or less, exclusively confined to the Arctic and Sub- 

 Arctic Seas ; while others, like the Pigmy Whale {JVeodalcena)^ 

 are equally characteristic of the Southern Seas. In conse- 

 quence of these widely roaming habits of so many members of 

 the Order, it is somewhat difficult to say how many species 

 have a right to be included in the British Fauna. We must, 

 however, regard all such as habitually frequent our coasts as 

 entitled to a place in our Fauna ; while in the case of those 

 occurring only now and again, we must rather look upon them 

 as accidental visitors. Still, however, no "hard-and-fast line" can 

 be drawn in this respect. 



THE WHALE-BONE WHALES. 

 FAMILY BAL^NID^. 



This Family, which includes the whole of the larger Whales, 

 with the exception of the Sperm-Whale, is at once distinguished 

 from all the others by the total absence of teeth, and the 

 presence of that peculiar substance in the palate known as 

 whale-bone or baleen. The nostrils open by two slit-like 

 apertures. 



Since the structure, arrangement, and mode of action of 

 whale-bone has been described in so many works, it will be 

 quite unnecessary that this should be recapitulated here ; and 



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