606 MANUAL OF ZOOLOGY. 



are always long and pointed, and the molars are generally 

 furnished with sharp cutting edges. 



The section Pinnigrada includes the two families of the 

 Seals (Phocida) and Walruses (Trichecidee). The Seals are 

 distinguished by having incisor teeth in both jaws, and by the 

 fact that the canine teeth are not disproportionately developed. 

 They form a very numerous family, of which species are found 

 in almost every sea out of the limits of the tropics. They 

 abound, however, especially in the seas of the Arctic and 

 Antarctic regions. They live for the most part upon fish, and 

 when awake, spend the greater part of their time in the water, 

 only coming on land to bask and sleep in the sun and to suckle 

 their young. They appear to be universally polygamous. The 

 body is covered with a short fur, interspersed with long bristly 



Fig. 260. The Greenland Seal (Phoca Groenlaitdica), 



hairs ; and the lips are furnished with long whiskers, which act 

 as organs of touch. The Seals are very largely captured for 

 the sake of their blubber. 



The only common British Seal is the Phoca vitulina, which 

 occurs not uncommonly on the northern shores of Scotland. 

 It is yellowish-grey in colour, and measures from three to five 

 feet in length. Other Seals attain a much greater length the 

 Great Seal measuring from eight to, ten feet, and the Bottle- 

 nosed Seal reaching a length of from twenty to twenty-five feet. 

 The only Seals which possess external ears constitute the genus 

 Otaria, and are almost exclusively confined to the seas of the 

 southern hemisphere. 



The second family of the Pinnigrade Carnivores is that of 

 the Trichedda -, comprising only the Walrus or Morse (Triche- 



