VBETEBRAL COLUMN 57 



that the rib occupies in the thoracic vertebrae. It is about as long as 

 the other element, but is directed ventrally and also slightly laterally 

 and toward the tail. Its cephalo-caudal diameter is much greater than 

 that of the dorsal branch, and of the common basal portion. It is 

 divided by an emargination of varying depth into cephalic and 

 caudal parts (Fig. 27), thus producing with the transverse element 

 three branches to the transverse process. 



CHARACTERS OF THE REMAINING CERVICAL VERTEBRA. 



The Seventh Cervical Vertebra has no arterial canal in its trans- 

 verse process. Its spinous process is much longer than the spinous 

 processes of the other cervicals, and points dorsally. Its transverse 

 process is a simple bar directed transversely and slightly ventrally. 

 The seventh cervical differs from the first thoracic in that it bears 



FIG. 30. 



Axis. 



Fifth. 



With Skull. 



With Sixth. 



FIRST FIVE CERVICAL VERTEBR.E, SIDE VIEW. 



on the ventral surface of its transverse process no articular facet for 

 the tubercle of a rib. It differs from the sixth in the following 

 additional characters : The body has a greater transverse diameter, but 

 a smaller cephalo-caudal diameter. The pedicles are more extended 

 dorso-ventrally and from the cephalic to the caudal end. The laminae 

 slope more dorsally toward the spine, and the neural canal is larger 

 and more arched. The cephalic articular processes are longer. 



The Fifth Cervical Vertebra (Figs. 29, 30, 31) closely resembles 

 the sixth and the fourth. It can be distinguished from the sixth by 

 the transverse process, which is not divided at the end into three 

 branches. 



