34 THE SKELETON OF THE HORSE 
THE CERVICAL VERTEBRE 
The cervical vertebrie (Vertebree cervicales) are seven in number. 
The first and second cervical vertebrae are highly modified in conformity with 
the special functions of support 
and movements of the head. 
The sixth and seventh present 
special characters, but do not 
differ greatly from the type. 
With the exception of the first, 
Spinous 
process Vertebral foramen 
Articular 
process they are quadrangular, mass- 
ive, and longer than the ver- 
rch tebrie of other regions; they 
; decrease in length from the 
Foramen’ second to the last. ‘The third, 
sarium fourth, and fifth have the fol- 
lowing characters: 
1. The body is long as 
Trans compared with those of other 
verse vertebrae. The ventral surface 
PROCESS presents a median ventral 
spine, which becomes more 
Head prominent as it is traced back- 
Fic. 9.—SrxtH Cervical VERTEBRA OF Horse; ANTERIOR VIEW. ward, and 1S tuberculate at its 
posterior end; it separates two 
concave areas. The dorsal sur- 
face has a flat central area which is narrow in the middle of the vertebrae, and wide 
at either end; it gives attachment to the dorsal longitudinal ligament. On either 
side of this area there is a groove which lodges the longitudinal spinal vein. These 
lateral grooves are connected about the middle of the surface by a transverse furrow, 
in which there are several for- 
amina through which veins 
emerge from the spongy sub- 
stance of the body. The an- 
terior extremity or head (Ca- 
put vertebre) has an oval 
articular surface which faces 
forward and downward; it is 
strongly convex, and wider 
above than below. The pos- 
Spinous process 
Vertebral 
foramen Articular 
| process 
terior extremity is larger and nck 
has a nearly circular cotyloid 
cavity (Fossa vertebrie). 
2. The arch is large and , 
3 E © Trans- 
strong. It is perforated on anne 
either side by a foramen which 
communicates with the for- 
amen transversarium. The 
vertebral notches are large. 
3. The articular processes 
are large. Their articular sur- 
faces are extensive, oval in outline, and slightly concave; the anterior ones are 
directed dorso-medially; the posterior, ventro-laterally. The remaining surface is 
mainly roughened for ligamentous and muscular attachment. A crest connects 
process 
ny Head 
=| : 
Ventral spine 
Fic. 10.—SrventH CervicaL VERTEBRA OF Horse; ANTERIOR VIEW. 
