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ANATOMY OF THE HORSE, 
horns, with which they are articulated. Each horn presents— 
two smooth polished surfaces , viz. an internal and an external 
side; two borders, an anterior and a posterior, the latter surmounted 
by a prominent crest; and two extremities; the supero-posterior 
has a cartilaginous junction with the hyoideal process of the 
petrous portion of the temporal bone, the infero-anterior, with the 
short horn. It gives attachment to the stylo-hyoideus and hyoi- 
deus magnus, and also to the pharynx. 
Connexion —With the temporal bone, larynx, pharynx, tongue, 
and some of the muscles of the neck. 
Development . —In the young animal the body itself is separa¬ 
ble into three pieces. 
the teeth; 
The instruments for the abscission and manducation of food. 
Number —Forty ; disposed in pairs; twenty in each jaw. 
Conformation— Conoid, or oblong, infixed within distinct alve¬ 
oles formed in the maxillee; whence we distinguish, in each tooth, 
a part without and a part within the socket: to the former portion 
we give the name of body , and that of face to the wearing surface 
of it; the latter is called the root , and the pointed extremity of it 
the fang. 
Structure. —The tooth is composed of two hard substances, 
distinct from each other in aspect as well as nature; viz. a dense, 
hard, solid bone , which is organic; and a still whiter and harder 
part, called enamel, which is inorganic. It is only the body of 
the tooth which is coated with enamel; the root is quite destitute 
of it: the former owes its polished whiteness to it. Upon the face 
it is variously disposed, according to the form of the tooth, from 
which it sinks, more or less deeply, into the heart of all teeth 
excepting the tusks; forming thereby small funnel-shaped ena- 
mellated cavities, called the infundibula, whose mouths, named 
the pits, are indicated by the black marks upon the faces. 
The tooth is essentially formed of bone, the enamel being no 
more than a covering or defence to it. Within the bone is a 
cavity, corresponding in shape and dimensions to the tooth itself. 
This, the cavity of the tooth, contains the pulp, inclosed within 
the membrane of the tooth: these are amply furnished with blood¬ 
vessels and nerves, which gain admission through the points of 
the fangs. 
Distribution —Into three classes : 1st, the Incisors, or cutting 
teeth ; 2d, the Molares, or grinding teeth ; 3d, the Canini , or tusks. 
The incisors, twelve in number, are ranged in parabolic 
curves in the anteriormost parts of the jaws. —Form —A bent 
cone, of which the face is the basis ; the fang, the apex. Face, 
