THE HORSE - 59 



became fixed in the inheritances. When, gaining strength 

 and coming to possess a more important place in the world, 

 these ancient tree-dwellers were able to occupy the ground 

 which of old had been possessed by the great reptiles, the 

 limbs that had served well for an arboreal life had to 

 undergo many changes in order to fit them for progression 

 in the new realm. 



If we watch the progress of a bear over the surface of the 

 ground, we readily perceive how lumbering is its gait and how 

 poor the speed which it attains. Its slow and shambling 

 movement is due to the fact that it has the tree-climbing 

 foot, and is not well fitted for motion such as is required in 

 running. To attain anything like speed in this exercise it is 

 necessary to support the body on the tips of the toes. Every 

 man who has gained any skill in this art knows full well how 

 incompetent he is if he tries to run with rapidity in the flat- 

 footed manner. The bear cannot essay this method of pro- 

 gression on the toe-tips because its loose-jointed feet cannot 

 be made to support its heavy body. In this way arose the 

 necessity of developing a peculiar kind of foot when that part 

 had to serve for rapid locomotion. The experiments to this 

 end have been numerous and varied. Thus in the elephants, 

 which retain the originally numerous toes, the bones of these 

 members are planted in an upright position and tied together 

 with such strong muscles and sinews, that the foot parts have 

 something like the solidity and strength of the upper portions 

 of the legs. In the single-hoofed or horse-like forms, and in 

 the cloven-footed animals, other series of experiments have 

 been tried which in the end have proved most successful, 

 giving us animals with the speediest movements of any 

 animals except the creatures of the air. 



