33 



height of the neural canal. The bases of the ribs still remain in a few cases. In the 

 supposed late cervical, the costal facet extends upward on to the base of the neural arch. 

 Two large foramina, placed one on either side of the median line of the lower surface 

 and separated by a low ridge, are connected with a passage that opens into the neural 

 canal by two separate apertures. The neural canal is about as high as it is wide. 



Measii,rements. 



A small vertebra from anterior end of series : M. 



Length of centrum -045 



Breadth of articular face . . . -065 



Height of same ^ -040 



Width of neural canal -012 



A larger vertebra from posterior end of series : 



Length of centrum . . -044 



Breadth of articular face -072 



Height of articular face -045 



Width of neural canal -015 



Height of costal face , . , -025 



Breadth of same -022 



According to Cope, Discosaurus is specifically identical with this genus. "Whilst under 

 the generic name Cimoliasaurus, Lydekker* has included Brimosaurus, Leidy, and Elas- 

 mosaurus and Polycotylus of Cope. 



Belly River series, Red Deer river, below Berry creek, 1898 and 1901. 



CHELONIA. 



TRIONYCHID^. 



Trionyx, GeofFroy. 



Trionyx foveatus, Leidy. 



Plate I, figs. 1 and 2. 



Trionyx Joveatus, Leidy. 1860. Trans. Amer. Philos. Soc. vol. xi, p. 148, pi. xi, fi^'s. I and 2. 



" " Lambe. 1902. Geol. Survey of Canada, Summary Report for 1901, p. 81, pis. i 



and n. 



Trionyx foveatus was originally described by Leidy from small fragments of costal and 

 sternal bones from the Judith River beds of Nebraska. 



A carapace, from the Belly River series of the Red Deer river district, lacks only the 

 nuchal plate, which unfortunately was missing. 



*Cat. of Fo3s. Reptilia and Amphibia, Brit. JMus., pt. II, p. 211, 1889. 

 5 



