68 
ANATOMY OF THE HORSE. 
sockets for the reception of the heads of the ribs. The verte¬ 
bral foramen is of less diameter than in the neck, and is oval 
from side to side. Spinous process, long and flattened on its 
sides; thick and triangular or prismatic at its root; presenting 
a sharpened edge forwards, a flat or obtuse border backwards ; 
thick, irregular, and tuberous at its summit. Transverse pro¬ 
cesses, short and thick, incurvated upwards, and tuberous at 
their extremities; their sides presenting circular articulatory 
surfaces for the tubercles of the ribs. Articular processes, very 
short and proceeding from the roof of the arch : the anterior, face 
upwards ; the posterior, downwards and backwards. There are 
only two notches, and these are smaller than those of the cer¬ 
vical ; they are situated between the posterior articulatory pro¬ 
cesses and the costal surfaces upon the body. 
LUMBAR VERTEBRA. 
Volume, between that of the cervical and dorsal.— Nufnber, 
in some subjects five, in others six. Body, short and thick; 
flattened superiorly, prominent inferiorly; and bearing much re¬ 
semblance to that of a dorsal, only that it is something larger, 
is oval from side to side, and thicker anteriorly than posteriorly : 
its articulatory, convexity in front and concavity behind assume 
also rather an oval than a heart shape. The vertebral hole is 
simi-circular, and of larger diameter than in the dorsal verte¬ 
brae. The spinous process is shorter than most of the dorsal; 
has broad flat sides; protuberates at the front of its summit; and 
stands erect with a very slight inclination forwards. The trans¬ 
verse processes, stand out horizontally, at right angles from the 
body, slightly inclined in the form of arches ; are long and 
broad ; flattened above and below; and gibbous at their extremi¬ 
ties. The articulatory processes, though small when compared 
with the cervical, are larger than the dorsal; they project from 
the roof of the arch in the horizontal direction: the anterior, 
protuberate at their extremities, are wude apart, and present 
concavities inwards ; the posterior, are nearer together,'and pre¬ 
sent convexities outwards. The notches are similar to those in 
the dorsal vertebrae. 
PECULIARITIES OF THE VERTEBRAi. 
Of the cervical, four vertebrae are distinguished by peculiar 
characters. 
The First Vertebra, inappropriately named the atlas, 
(for the head is suspended from it instead of being supported by 
