250 ANATOMY AND PHYSIOLOGY OF THE HORSE*S FOOT. 
almost defies wear and external injury ; it is light, and, being 
narrow and hollow, it can he solidly implanted on uneven, 
stony surfaces. The hoof shows the same adaptation to 
circumstances as the other parts of the animal. 
But the horse reared in a low-lying marshy locality is the 
very opposite of the light, agile, wiry steed. Physically soft 
and unenduring, this animal is massive ; it has a hoof wide 
and flat, the frog spongy and voluminous, and the horn gene- 
rally pulpy and incapable of successfully resisting wear on 
any other soil but that on which it has been formed. And 
yet this organ is well fitted for locomotion in its particular 
region, and is a perfect agent of support for the large phleg- 
matic creature that inhabits these humid, marshy districts ; 
the widely expanded base, with its flat sole, sinks but little 
in the yielding soil, and the frog, standing out so prominently 
from its surface, and in shape somewhat like a ploughshare, 
acts as a stay to prevent slipping. Wear and concussion being 
reduced to a minimum on such a surface, the horn is porous, 
slowly secreted, and soft. Had it been solid it would have 
been much heavier, and there was no need for its rapid 
growth or great hardness. The shape of the hoof and cha- 
racter of the horn is most wisely adapted to the situation and 
mode of life of the animal. Suddenly transport the dry, 
nervous, condensed horse, with its typical foot, to the marshy 
region, and what shall we behold ? What will become of 
the light, thin limbs, with their narrow, hollow-based hoof? 
Or travel the large, heavy, oedematous creature from his 
damp, springy pasture-land or muddy flats, all at once to the 
rugged stony mountain paths and the hot arid atmosphere, 
and witness his attempts at locomotion ! The one would 
flounder deeply in the treacherous ground, while the other 
would limp painfully along for but a short distance before he 
dropped down incapable of further journeying.* Butin time 
* We have numerous examples of this adaptability of the feet of other 
animals, besides the horse, to the ground over which they have to travel, 
though in the immediate progenitor of this animal himself, the tridactylous 
miocene hipparion, we have an excellent illustration. The hoofs of the 
reindeer are wonderfully adapted to the country it inhabits. Instead of 
being narrow and pointed, like those of the roebuck or the fallow-deer, they 
are remarkably broad, flat, and spreading ; and when it sets down its foot 
it has the power of contracting or spreading its hoofs in a greater or less 
degree, according to the nature of the surface on which it moves. When 
snow is on the ground and in a soft state the broadness of the hoofs it then 
spreads out, so as almost to equal in size those of a horse, gives it a firmer 
support on the snow, and hinders it from sinking so deep as it would other- 
wise do . — Be Capell Brooke , ‘ Travels in Lapland/ p. 84 . 
And the buffalo exhibits a similar fitness to traverse muddy regions. Sir 
J. E. Tennent says— “ There is a peculiarity in the formation of its foot, 
