BONES OF THE HEAD. 
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23, 23. The pastern of the hind feet, including the upper and 
larger bone, (fig. 23,) the lower pastern, (fig. 25,) and 
the coffin-bone, (fig. 24.) 
26, 26. The caudal vertebrae, or bones of the tail. 
BONES OF THE HEAD. 
PLATE VIII. Fig. 2 and 3. 
The head contains the brain and other important organs 
of sense. It is divided by anatomists into two parts, 
namely, the skull and the face. The skull, or cranium, 
is that portion in which the brain is situate ; and the bones 
in which it is enveloped are destined for its protection. 
This division consists of nine bones : the two frontal bones, 
a, a; two parietal, c 9 c; two temporal, d, d; the occipital, 
g; the ethmoid ; and sphenoid : the two latter are situate 
at the base of the skull, and are not visible in a front view, 
but their position will be seen in fig. 3, plate iii., the 
ethmoid, or sieve-like bone, immediately above k, and 
sphenoid, l. These nine bones are separated in the foal 
at an early period of its existence ; but soon after birth 
they are firmly united together by the sutures, at which 
parts they are so strong that fracture seldom or never occurs 
there. 
There is a beautiful evidence of design in this division 
of the head into so many bones. When the foetus of the 
foal in the womb first assumes a form, and may be said 
to be in life, this portion of the skull is merely a jelly-like 
consistence, which is gradually changed into a harder sub¬ 
stance, called cartilage ; and previous to the birth of the 
animal much of this cartilaginous substance is carried off 
by certain vessels emanating from the brain, called ab¬ 
sorbents, and bone is deposited in its stead. In all the 
flat bones, such as those of the head, this deposit takes 
