THE CEIiVICAL VERTEBRAE. 



75 



The fourth vertebra in Tinoceras f/rande is siiTiilar, in its more 

 important characters, altliongh proportionally shorter, and its principal 

 features are well shown in fijjures 87 and 88, helow. 



Figure 87. — Fourth cervical vertebra of Tinoceras grande, Marsli (No. 104(1); front view. 

 Figure 88. — The same vertebra; side view. 



/. lateral foramen; nc. neural canal; z. .nulerior zygapophyais ; z'. posterior zygapophysis. 

 Both figures are one-fourth natural size. 



The main dimensions of the fourth vertebra in one species each of 

 IHnoceras and Tinoceras are given below. 



Measurements of Fourth Cervical J^ertebra. {Dinoceras mirahile^ No. 1255.) 



m. 

 Length of floor of neural canal, .__. .055 



Length of centrum, along under surface, . .054 



Tran.sverse diameter of anterior epiphysis, 079 



Vertical diameter of anterior epiphysis, .075 



Transverse diameter of posterior epiphysis, ._, .091 



Vertical diameter of posterior epiphysis, .075 



Antero-posterior extent of zygapophyses, ... .089 



Diameter of lateral foramen, .024 



Transverse diameter of neural canal, ._ .04.3 



Measurements of Fourth Cervical Yertehra. [Tinoceras t/rande, No. 1040.) 



Length of floor of neural canal, __ .042 



Length of centrum, on under surface of vertebra, _. .045 



Transverse diameter of anterior face, .100 



Vertical diameter of anterior face, .094 



Transverse diameter of neural can.al, .055 



Vertical diameter of neural canal, _ .040 



Diameters of lateral foramen, .025-015 



