16 THE SKELETON OF THE CAT. 
tubercle of the transverse process, and by a median tubercle on 
the cranial border of the vertebral arch. 
The fourth by the spinous process directed dorsad, and the 
short thick tubercle of the transverse process not trifid. 
The fifth by the spinous process directed craniad, and the 
more slender spine-like tubercle of the transverse process not 
trifid. 
The sixth by the trifid transverse process. 
The seventh by the long spinous process and the slender 
-simple transverse process, and by the usual absence of the 
foramen transversarium. 
LIGAMENTS OF THE VERTEBRAL COLUMN. 
Fibro-cartilagines intervertebrales.—The separate verte- 
bre (except the atlas and axis) are united by the disk-shaped 
intervertebral fibro-cartilages, which are situated between the 
centra of the vertebree. Each consists of a central pulpy por- 
tion and a fibrous outer portion, covered by strong intercross- 
ing tendinous fibers which unite with the periosteum of the 
vertebre. 
Ligamentum longitudinale anterius.—On the ventral 
face of the centra of the vertebrae, from the atlas to the 
sacrum, lies a longitudinal ligament, the anterior longitudinal 
ligament. It is very small, almost rudimentary, in the cervi- 
cal region: large and strong in the thoracic and lumbar regions. 
Ligamentum longitudinale posterius (Fig. 14, a). —A 
corresponding ligament (posterior longitudinal ligament) lies 
on the dorsal surface of the centra (therefore within the verte- 
bral canal). It is enlarged between each pair of vertebre and 
closely united to the intervertebral fibro-cartilages. 
Ligamentum supraspinale.— Between the tips of the 
spinous processes of the thoracic and lumbar vertebrz extend 
ligamentous fibers. They are not united to form a distinct 
band, and can hardly be distinguished from the numerous 
tendinous fibers of the supraspinous muscles. Together they 
represent the supraspinous ligament. From the tip of the 
spinous process of the first thoracic vertebra to the caudal end 
of the spine of the axis extends a slender strand representing 
