394 



The Bird 



When one trains in college for a long-distance race, 

 one rule to observe is, never touch your heels to the ground ; 

 run wholly on the ball of the foot. Untold centuries 

 ago, wise old Nature whispered the very same direction 

 to those of her children who had most need to run for 

 their lives in life's great race, and down through the 

 ages some of them have never broken training. When 



an animal acquires 

 great speed in running 

 or leaping, there is a 

 tendency for one toe 

 to become greatly en- 

 larged at the expense 

 of the others, as is 

 seen in the case of the 

 horse, the kangaroo, 

 and the ostrich. 



In the horse only 

 the middle toe is 

 functional, the second 

 and fourth having de- 

 generated into the 

 small splint-bones at 



FIG. 308. Feet and legs of Cassowary. 



the side of the leg. The kangaroo progresses upon 

 the fourth and fifth toes, the second and third being 

 small and skin-bound. The ostrich has but two toes, 

 one of which, the third, as in the case of the horse, is 

 very large and armed with a thick claw, which, hoof- 

 like, grows close to the toe. This toe supports most of 

 the bird's weight, while the fourth or outer toe is only 



