DISSECTING MANUAL. 



idal, and occupies the body of the superior maxilla. The 

 frontal sinuses lie, one on either side, between the inner and 

 outer tables of the frontal, over the root of the nose and ex- 

 tending outward. [174] 



CERVICAL VERTEBRA. 



General Characteristics. There are seven cervical verte- 

 brae. The bodies are widest transversely, and highest behind ; 

 transversely the upper surface is concave, and the lower sur- 

 face convex. The pedicles spring from the sides of the bodies 

 behind; the superior and inferior notches are nearly equal in 

 depth. The laminae are long and wide. The spinal foramen is 

 triangular. The transverse processes each consist of two parts ; 

 these enclose the vertebrarterial foramen and end in two tu- 

 bercles (anterior and posterior) , separated above by a groove. 

 The spinous processes are short, bifid, and directed downward. 

 The articular processes lie on the junction of the pedicles and 

 laminae; the superior facets are circular and look upward and 

 backward, the inferior downward and forward. [76] 



Atlas (First Vertebra) . This has neither body nor spinous 

 process, but consists of two lateral masses united by two 

 arches. Each lateral mass is elongated and approximated to 

 its fellow in front; on its upper surface is an oval facet, con- 

 cave antero-posteriorly and inclined inward ; on its under sur- 

 face there is a circular facet. The anterior arch is compressed 

 laterally; mesially it is thickened and presents a prominence 

 (anterior tubercle) in front, and a circular facet (for the odon- 

 toid process) behind. On the inner surface of each lateral 

 mass is a tubercle for the transverse ligament; on the outer 

 side the transverse process arises by two roots, enclosing the 

 foramen, but its end is not bifid. The posterior arch arises 

 from both the lateral mass and the posterior root of the trans- 

 verse process; on its upper surface anteriorly is a transverse 

 groove; mesially it is thickened and has a projection (posterior 

 tubercle) behind. [77] 



[18] 



