78 DINOCERATA. 



Measurements of Sixth Cervical Vertebra. (Dinoceras niirabile. No. 1255.) 



m. 

 Length of floor of neural canal, .049 



Length of centrum, along under surface, .055 



Transverse diameter of neural canal, ... . .051 



Vertical diameter of anterior epiphysis, _. .076 



Transverse diameter of posterior ejHphysis, : . .088 



Vertical diameter of posterior epijjhysis, .. 078 



Antero-posterior extent of zygapophyses,. ., . .087 



3feasure?nents of Sixth Cervical Vertebra. {^Dinoceras ciineum, No. 10-12.) 



m. 

 Transverse diameter of centrum, ^ .111 



Length of centrum, along under surface, .. .05.3 



Transverse diameter of neural canal, _. .071 



Vertical diameter of neural canal (approximate), .044 



Transverse diameter of anterior face of centrum, .100 



Vertical diameter of anterior face of centrum, .. .092 



Diameter of vertebra, across pre-zygapophyses (approximate), . _ .170 



Diameters of lateral foramen, . . .022-034 



Antero-posterior diameter of pedicel, .026 



The Seventh Vertebra. (Plate XXII, figures 6-10.) 



The seventh cervical vertebra of Dinoceras ndrabile (number 1255) 

 has the anterior fece of the centrum nearly circular. The posterior face 

 is expanded transversely, and its lateral margins are cut by the facets for 

 tlie head of the first rib. The neural canal is distinctly sub-cordate in 

 outline, and there is a rudimentary neural spine. The lateral foramen 

 has disappeared, but the transverse process is notched below for the 

 passage of the vertebral artery. These characters are shown in Plate 

 XXII, figures S and 10. 



Measurements of Seventh Cervical Vertebra. {Dinoceras tnirabile. No. 1255.) 



m. 

 Length of floor of neural canal, .046 



Length of centrum, along under surface, 051 



Transverse diameter of neural canal, .061 



Vertical diameter of neural canal (approximate), .046 



Transvei'se diameter of anterior articular face (approximate), .076 



Transverse diameter of posterior articular face (approximate), 075 



Antero-posterior extent of zygapophyses, ,084 



Diameters of articulation for first rib, 022-035 



Diameter, across transverse processes (approximate),. 185 



