ANATOMY OF THE HORSE. 
67 
the sides over the body, so as to include its superior surface; 
and this surmounted by the spinous process ; lastly, the verte¬ 
bral, spinal, or medullary hole. 2nd, The sides present two 
transverse processes, jutting outward ; four articulatory pro¬ 
cesses, two anterior and two posterior, having smooth surfaces 
for articulation with those of the vertebrse next to them; four 
notches, the excavations between the arch and the body, con¬ 
stituting, by opposition with others in the contiguous vertebrae, 
the holes of conjugation. 
CERVICAL VERTEBRA. 
Larger than the others, and differ more remarkably in their 
individual conformation.—In number, seven; and named ac¬ 
cording to their numerical order, beginning from the head : the 
first, however, has got the designation of atlas, and the second, 
of axis or vertebra dentata.—In figure, quadrangular. Body, 
oblong; anterior surface of it, smooth, convex, heart-shaped, 
apex turned downwards; posterior surface, correspondently 
concave. The vertebral hole is larger than in the other classes, 
and semi-oval in figure. Two spinous processesthe crest or 
superior one is bifid, cleft and divergent posteriorly, united at a 
sharp angle anteriorly; the inferior (the additional) spinous 
process is curved like an S reversed and inclined ; being con¬ 
vex and prominent posteriorly, sharp-edged and curved upwards 
anteriorly. The transverse processes are very broad, but short, 
arise from the body as well as the arch, are bifid, presenting 
four projecting ends, two forwards, two backwards, and are 
each perforated by a foramen, which transmits the vertebral ar¬ 
tery and vein. The articular processes are large, directed hori¬ 
zontally forwards and backwards, and present broad surfaces 
for articulation; those on the anterior looking upwards and 
inwards, those of the posterior downwards and outwards. The 
notches are found between the articular processes and the body. 
DORSAL VERTEBRA. 
Volume, less than that of either of the other classes.— Num¬ 
ber, eighteen ; (in some instances, nineteen;) distinguished by 
their numerical order, counting from the neck backwards. 
Body, small; short, thick, and semi-circular; flattened supe¬ 
riorly, prominent and edged inferiorly; anteriorly, smooth, con¬ 
vex, and heart-shaped; posteriorly, correspondently concave. 
At the junction of the arch with the body are situated four 
small cup-shaped articular surfaces, two presented forwards, two 
backwards, which in conjunction with those next to them form 
2 
