LAW OF SIMPLIFICATION OF FEET. 



187 



the liorse, viz: by manifesting the two toes fully de- 

 veloped, Avhich were rudimental in the more simple foot; 

 the cuboides, &, being proportionally extended to support 

 the fifth toe, r, as well as the fourth, iv ; the second toe, 

 ?7, articulates, as usual, with a distinct tarsal bone. In 

 the elephant (Fig. 39), where a fifth digit is added, 



m 



HIPPOPOTAMUS 



answering to our first or great toe, I, there is also a dis- 

 tinct carpal bone, called the " entocuneiform," c?*, and the 

 tarsus presents, as in other pentadactyle mammals, all the 

 bones which are seen in the human tarsus, viz: the 

 astragalus, a, the calcaneum, c, the scaphoides, 5, the ento- 

 cuneiform, cz, the mesocuneiform, cm, the ectocuueiform, 

 cc^ and the cuboides, h. 



The course of the simplification of the pentadactyle 

 foot or hand is first a diminution and removal of the 

 innermost digit, ^ ; next of the outermost, v ; then of the 

 second, ii; and lastly of the fourth, iv ; the third or middle 

 toe, m, being the most constant and important of the five 

 toes. The same law or progress of simplification prevails 

 in the fore-foot or hand. The thumb is the first to dis- 

 appear, then the little finger, and the middle finger is the 



