70 



SPECIAL ANATOMY. 



The most particular characters by which to recognize the different vertebrae, 

 immediately, are : 



1. Cervical vert. Foram. vertebrakf the extremity of the proc. Spinosus. 



2. Dorsal vert. Articular surface upon the body,- articular fossa on the 

 proc. transversus. 



3. Lumbar vert. The want of those characters peculiar to the cervical 

 and dorsal vertebrae. By the transverse processes we can most easily 

 distinguish the vertebrae of one region from those of another. 



T7. Separate Vertebrae. 



I. Atlas, first cervical, lies like a ring at the circumference of the foramen 

 Magnum, close to the skull, which it supports; consists of an anterior and a 

 posterior segment. Arctis anterior, in the place of the vertebral body, is flat, 

 convex anteriorly with a tubercle, tuberculum anterius, and on the concave 

 posterior surface provided with a flat, egg-shaped, articular fossa for the 

 odontoid process of the second cerv. vertebra. The lateral portions, massae 

 laterales, are strong, present above the concave fossds condyloidese, correspond- 

 ing to the superior oblique processes, for the proc. condi/loid. occipitis ; below 

 the round, flat, proc. obliqui inferiores, for the Epistropheus ; upon the internal 

 surfaces of either side a tubercle, tuberculum laterale, for the ligam. trans- 

 versum. Arcus posterior, the largest part of the Atlas, consists of two narrow 

 plates, which meet together at an angle and terminate with the tuberculum 



