CARNIVORA. 605 



In all the Carnivora the clavicles are either altogether want- 

 ing, or are quite rudimentary. The toes are provided with 

 sharp curved claws. The teats are abdominal ; and the pla- 

 centa is deciduate and zonular. 



The order Carnivora is divided into three very natural sec- 

 tions : 



Section I. Pinnigrada or Pinnipedia. This section com- 

 prises the Seals and Walruses, in which the fore and hind 

 limbs are short, and are expanded into broad webbed swim- 

 ming-paddles (fig. 259, B). The hind-feet are placed very far 

 back, nearly in a line with the axis of the body, and they are 

 more or less tied down to the tail by the integuments. 



Section II. Plantigrada. This section comprises the Bears 

 and their allies, in which the whole, or nearly the whole, of 

 the foot is applied to the ground, so that the animal walks 

 upon the soles of the feet (fig. 259, A). 



Section III. Digitigrada. This section comprises the Lions, 

 Tigers, Cats, Dogs, &c., in which the heel of the foot is raised 

 entirely off the ground, and the animal walks upon the tips of 

 the toes (fig. 259, C). 



SECTION I. PINNIGRADA or PINNIPEDIA. This section of 

 the Carnivora comprises the amphibious Seals and Walruses, 

 which differ from the typical Carnivores merely in points con- 

 nected with their semi-aquatic mode of life. The body in 

 these forms is elongated and somewhat fish - like in shape, 

 covered with a short dense fur or harsh hairs, and terminated 

 behind by a short conical tail. All the four limbs are present, 

 but are very short, and the five toes of each foot are united 

 together by the skin, so that the feet form powerful swimming- 

 paddles. The hind-feet are of large size, and are placed far 

 back, their axis nearly coinciding with that of the body (figs. 

 259, 260). From this circumstance, and from the fact that the 

 integument often extends between the hind-legs and the sides 

 of the short tail, the hinder end of the body forms an admir- 

 able swimming apparatus, similar in its action to the horizontal 

 tail-fin of the Cetacea and Sirenia. The tips of the toes are 

 furnished with strong claws, but their powers of terrestrial loco- 

 motion are very limited. On land, in fact, the Seals can only 

 drag themselves along laboriously, chiefly by the contractions 

 of the abdominal muscles. The ears are of small size, and 

 are mostly only indicated by small apertures, which the animal 

 has the power of closing when under water. The bones are 

 light and spongy, and beneath the skin is a layer of fat or 

 blubber. The dentition varies, but teeth of three kinds are 

 always present, in the young animal at any rate. The canines 



