MAN'S NEAR RELATIVES {MAMMALS). 
227 
some care, be found even in a hand or fore foot so 
much specialized as that of the horse. 
Hands and Feet. As we have already found, the 
bones of the hind feet closely resemble those of the fore 
feet, or, in other words, hands and feet are built on the 
same plan. The palm of the hand corresponds to the 
sole of the foot, showing the same ridges and callosities. 
Animals which put the whole sole of the foot, from toe 
Fig. 190. —Finger of Man and of Horse. After Flower. a t callous; b, 
cushion; c, nail. 
to heel, on the ground when they walk are said to be 
plantigrade animals. Quadrupeds, like the bear, which 
walk in this way have a somewhat awkward gait. The' 
more graceful and easy runners among beasts walk on 
the ends of their toes. These are said to be digitigrade 
animals. The horse presents an extreme illustration 
of the digitigrade foot, walking as he does on the ends 
of his middle toes and middle fingers. We, ourselves, 
walk on the whole sole of the foot, but when we run 
we rise on the toes. If we should attempt to walk on 
all fours, bearing the weight of the body on soles and 
