The Alligator and Its Allies 



the hypapophysis. On each side of the centrum, 

 near its anterior end, is a facet with which the lower 

 branch (capitulum) of the rib articulates. The 

 neural arch is strongly developed and is extended 

 dorsally into a prominent neural spine and on each 



6- 



10- 



FIG. 17. FIRST FOUR CERVICAL VERTEBR/E OF A CROCODILE 



(C. vulgaris). (From Reynolds, partly after Von Zittel.) 



1. pro-atlas. 7. 



2. lateral portion of atlas. 



3. odontoid process. 8. 



4. ventral portion of atlas. 9. 



5. neural spine of axis. 10. 



6. postzygapophysis of fourth 



vertebra. 



tubercular portion of fourth 

 cervical rib. 



first cervical rib. 



second cervical rib. 



convex posterior Burface of cen- 

 trum of fourth vertebra. , 



side as a short, blunt, transverse process with which 

 the tubercle or upper branch of the rib articulates. 

 Posteriorly the arch is notched on each side to form 

 the openings for the exit of the spinal nerves. Pro- 

 jecting dorsally and anteriorly from the arch are 

 two short processes which bear the medially and 

 dorsally facing prezygapophyses (Fig. 17). Just 

 caudad to these processes are somewhat shorter 



