MERRTAM: TRIASSIC ICHTHYOSAURI A. 



123 



Tibia. 



Greatest, length 1(1() 



Transverse diameter of proximal end 14;; 



Transverse diameter of median region 64 



Transverse diameter of distal end ]0;$ 



Fibula. 



( I reatest length 1 - ) - 



Transverse diameter of proximal end 82 



Transverse diameter of median region 78 



Transverse diameter of distal end 132 



Mesopodial ( ?). 



Anteroposterior diameter 46 



Transverse diameter 42 



CYMBOSPONDYLUS PISCOSUS Leidy. 



('ifnt/>xi>i>iidylus piscosim Leidy, Proc. Philacl. Acad. Sc., 1868, vol. 20, p. 178. 

 Cymbospondylus piscosus (Merriam), Univ. Calif. Publ., vol. 3, p. 104. 



Anterior and posterior faces of dor- 

 sal vertebral centra deeply and regu- 

 larly concave from the periphery to the 

 center of the face. Length of dorsal 

 vertebral centra equaling more than 

 half of the height. 



Known only from a single specimen 

 found in the Middle Triassic near New 

 Pass, about thirty miles west of Austin, 

 Nevada. 



This species is known only from a 

 single specimen consisting of one nearly 

 complete dorsal vertebra with parts of 

 four others. No similar material has 

 been observed in the collections from 

 the West Humboldt Range, and a care- 

 ful examination of the type locality has 

 not resulted in the discovery of other 

 specimens. 



135 



136 



Fig. 135. Cymbospondylus pctrinus Leidy Antero- 

 posterior section of a middle or anterior dorsal 

 vertebra, X %. 



Fig. 136. Cymbospondyl-us piscosus Leidy. Antero- 

 posterior section of an anterior or middle dorsal 

 vertebra, X %. 



