OSSEOUS SYSTEM OF MAMMALIA. 



95 



the outer toe on each side being, indeed, shorter than the two middle ones, 

 but quite as perfect. The ruminant has two toes only ; it is truly cloven- 

 footed : still, at the extremity of the canon bone, will be often found 

 the vestiges of a lateral toe on each side, both in the skeleton and in 

 the living animal : it consists of a sort of spur, or rudimentary hoof, 

 supported by one or two little osseous stylets. This circumstance has 

 led some to object to Cuvier's assertion, that, wherever we see the track of 

 a cloven hoof, we may be sure that a ruminating animal has passed : be- 

 cause it may be fancied that the 

 Hog is as much a cloven-footed, 

 or bisulcate animal, as the Deer. 

 Fig. 99 represents two truly 

 cloven feet, , b, compared with 

 the foot of the Hog, c. 



From terrestrial Mammalia, let us turn to those which inhabit the 

 ocean, and plough their way through its rolling waters the mighty 

 Cetacea, as the Grampus, and the Whale ; animals destitute of hinder 

 limbs, and in which the pair, analogous to the anterior limbs of other 

 mammals, are reduced to the condition of paddles, being utterly des- 

 titute of the slightest power of prehension. 



100 The annexed sketch (fig. 100) shews the hand and 



arm as exemplified in the paddle of the Dolphin. In 

 the living animal the bones of the hand are imbedded 

 in a cellular tissue, the whole being invested with a 

 covering of skin ; so that the phalanges of the fingers 

 are agglutinated together, and neither enjoy, nor need, 

 anything like independent motion : the organ is, in fact, 

 a mere paddle, or oar ; yet it has to be worked, with 

 vigour and celerity, in a medium far denser than air. 

 Hence the large expanse of the scapula, a, for the attach- 

 ment of voluminous muscles, and the thick arid solid 

 structure of every bone. The humerus, 6, is short 

 and massive, as are, also, the bones of the fore-arm, 

 viz., the radius, c, and ulna, d ; the carpal bones, e, form two rows, 

 and are succeeded by those of the metacarpus, /, which are flattened in 

 shape, and usually five in number. The number of the fingers, g, is the 

 same as that of the metacarpal bones ; but they vary, both in their 

 respective lengths, and in the number of phalangal portions of which they 

 respectively consist. Ordinarily, the portion analogous to the thumb 

 is composed of two phalanges ; sometimes, however, as in the Dolphin, 

 of only one. The phalanges in the fingers of the common Whale, are, 

 four for the second and third, five for the middle finger. In the com- 

 mon Dolphin the middle finger consists of five phalanges ; the second and 



