34 BRITISH MAMMALS 



the teats, which at other times are concealed in folds of the 

 skin, stand out, much swollen. The milk is said to be abundant, 

 and very rich. 



The dolphin is not one of those cetaceans that frequent the 

 Arctic regions. It is very rarely met with as far north as 

 Southern Greenland, and it is not common off the coast of Norway. 

 The chief home of the common species appears to be the Mediter- 

 ranean, though it also extends across the North Atlantic. In 

 British waters it frequents the Channel more than the North Sea, 

 and in the Channel it is very common. Its food is fish, especially 

 herrings and mackerel, and also jellyfish, small cuttlefish, and 

 crustaceans. It seems to be a creature of happy disposition, 

 perpetually romping in the water, and by no means afraid of man. 

 It constantly accompanies ships in large herds, and, indeed, is 

 more commonly seen even than the porpoise. Like its congeners, 

 it has a voice, which it is said to use in a gentle lowing sound. 



Tursiops tursio. The Bottle-nosed Dolphin 



The Bottle-nosed Dolphins differ from the true dolphins by 

 their somewhat larger size, and by the much shorter and less 

 prominent beak. This creature is very under-hung, the 

 upper jaw being quite short as compared with the lower jaw, while 

 the opening of the mouth begins much higher up in the head, 

 suggesting a faint resemblance to the whalebone whales. The 

 teeth are fewer than in the true dolphin — about twenty to twenty- 

 five on each side of each jaw. These teeth in the adult animal 

 become worn down to flat surfaces, except perhaps in the case of 

 one or two in the front of the jaw which retain their conical 

 shape. In colour the bottle-nosed dolphin is purplish-gray above 

 and gray or grayish-white on the under parts. The flippers are 

 shorter than in the common dolphin, the back fin is rather long, 

 but blunt-tipped. This creature is said to have a powerful voice, 

 like the bellowing of a bull. The range of the bottle-nosed 

 dolphin is very much that of the common dolphin, but in British 

 waters it is a much rarer animal. Specimens have been obtained 

 during the last hundred and twenty years from the Thames and 



