FOOT OF STEINBOK. 



301 



tendency to place the weight of the limb more on one 

 particular digit than on any other digit. The fact that the 

 feet of the tapir have undergone, practically, no modification 

 for several millions of years, proves that his conditions of life 

 at the present day are nearly the same as they were when 

 the ancestors of the horse, like those of the tapir, had four 

 hoofs on each front foot, and three on each hind one. Feet 

 like these, which, under the influence of pressure, had the 

 faculty of spreading out, were admirably suited for going 

 through soft ground similar to that over which the tapir still 



■mr^ c 



Fig. 395. — {After Gatidry^ FOOT OF SxElNBOK 



roams in a wild state ; for the increase of the area of support 

 thus offered by the feet, was a direct help in preventing the 

 animal from sinking too deeply in the mud over which he 

 travelled. It is evident that this lateral play of the digits 

 entailed loss of speed for progression on hard ground, on 

 account of expenditure of muscular power required to restore 

 them to their normal state, and from increased friction. The 

 less lateral play the digits would have, the faster would the 



