D VERTEBRATA. MAMMALIA. 



of seven* vertebrae, in the Giraffe, as in the Whale ; 

 the anterior ribs are connected with the breast-bone 

 (sternum] by cartilage ; the arm, or fore-leg, com- 

 mences in a shoulder-blade that is not jointed to the 

 skeleton, but imbedded in the flesh, often resting on 

 the sternum by an intermediate bone, called a cla- 

 vicle, or collar-bone. The limb jointed to the shoul- 

 der-blade consists of an arm, a fore-arm, and a hand, 

 the latter being composed of two ranges of small 

 bones, called the carpus, another range called the me- 

 tacarpus, and the fingers, each of which consists of 

 two or three bones, called phalanges. The hinder ex- 

 tremities in all except the Whale tribe (in which they 

 are wanting) are attached to the spine, by means of a 

 bony circle called \hepelvis. To this is attached the 

 thigh, succeeded by the two bones of the leg, and ter- 

 minated by bones resembling those of the fore-limb, 

 the tarsus, metatarsus, and toes. The skin is usually 

 defended by a covering of hair, but in many of the 

 larger races it is very scanty, and in the Cetacea, or 

 Whales, it is almost entirely wanting. The young are 

 in all cases produced alive, and are nourished for 

 some time by milk, a peculiar fluid secreted in the 

 mamnwe of the mother ; a distinctive character, which 

 has given name to the class. 



The subdivision of the Mammalia into orders is 

 founded on certain differences in the organs of touch, 

 (hands or feet,) and those connected with the taking 

 of food (teeth). The degree of perfection in the 



* The Three-toed Sloth, so long believed to have nine cervical vertebrae, 

 has been proved to be no exception to the universal rule. 



