THE MARINE CARNIVORA 



207 



pairs in the upper jaw and one pair in the lower, while the- molar 

 teeth are nearly all one-rooted, and are reduced in size and 

 degenerate in structure. The canines are strong and stout and 

 rather tusk-like, and the outer pair of upper incisors somewhat 

 resemble canines, so that, however much the outer teeth may be 

 reduced, the creature retains effective weapons in the canines and 

 upper incisors. The first and the fifth toes in the hind feet 

 exceed the others very much in length, and have the lobe of skin 

 prolonged for a considerable distance beyond the nail ; moreover, 

 the claws or nails on the hind toes are either absent or rudi- 

 mentary. The nose of the males is surmounted by a remarkable 

 appendage which can be inflated at will. This, in the species 

 represented in the British fauna, is developed into a great bladder, 

 shaped almost like a cockscomb, but in the elephant seal it 

 becomes a short proboscis. 



Cystophora cristata. THE HOODED OR BLADDER-NOSED SEAL 



The skull of this animal, to begin with, differs considerably in 

 shape from that of the normal seal. The ramus of the under 

 jaw is long, broad, and heavy. 

 The ridges round the eye orbits 

 are much developed, and the 

 cranium, or brain case, is pro- 

 portionately small. The bony 

 partition between the nostrils is 

 prolonged in front of the 

 orbits in a circular form 

 to support the huge air 

 bladder which terminates 

 inside the nasal opening of the 

 skull. The neck is somewhat 

 longer than in the common seals. 

 The adult male has the nose 



bladder much more developed HEAD OF HooDED SEAL 

 than the female. The bony partition in front of the eyes is 

 continued down to the aperture of the nostrils by a cartilaginous 



