SEALS. 235 



touch, the root of each bristle, as in the hind Carnivora, 

 being provided with a considerable nerve. 



The teeth are of the usual type of the order, specially 

 modified for the purpose of seizing the scaly and 

 slippery fish on which the Seal feeds. The canines are 

 strong and acute, the molars beset with pointed tuber- 

 cules of various forms, but all adapted to a piscivorous 

 diet ; in the genus Halichwrus those of the upper jaw are 

 remarkable for their simple and conical form. In the 

 seals the first or milk-teeth are merely rudimentary, 

 and are absorbed without cutting the gum, usually 

 during foetal life ; at the age of a week, according to 

 Prof. Flower, scarcely a trace of them remains. The 

 tongue is smooth, and slightly notched at the tip, and 

 the gullet is very dilatile. The stomach is simple in its 

 character, the intestine is very long, and is provided with 

 a coccum, and the liver is remarkable for the great 

 enlargement of the inferior vena cava. 



The whole skeleton is constructed on the same plan as 

 that of the other Carnivora. In the skull, the brain-case 

 is very broad and flattened, and the portion between the 

 orbits is much compressed. The internal bones of the 

 nostrils are extremely large and complicated, and the 

 division between them is well-developed, extending 

 forward in one genus [Cystophora) even in front of the 

 nasal bones. 



But perhaps the most striking peculiarity of the Seal 

 lies in the position and functions of the limbs, which are 

 not fitted to raise the body from the ground, and are 

 almost exclusively used in aquatic progression. Both 

 the fore and hind limbs are enclosed in the common 

 integument as far as the wrist and ankle-joints, and the 

 toes are connected together by complete webs. The 

 liind feet are extended backwards in tlie line of the 



