In. 



Lin. 



4. 



9. 



2. 



8.5 



3. 





9. 



11. 



AND AVES OF NORTH AMERICA. 43 



CIMOLIASAURUS MAGNUS, Leidy. 

 Pr. A. N. S., Phila., 1851, 335, 1854, 72. Cretaceous Rept. N. A. 25, tab. 00. 



This species has hitherto been known from vertebra} only. In connection with vertebrae of this species, I pro- 

 cared a long bone which has a near resemblance to the femur of Plesiosaurus. It indicates a paddle for motion in the 

 water, as has already been mentioned. 



The distal breadth is equal to If the length. It is distal compressed, but thick and with rounded margins. 

 The proximal portion is slightly reverted to the condyle, and compressed nearly at right angles to the distal extremity. 

 The condyle is flattened convex and oval in circumference. The tibial and fibular articular faces form a strong angle 

 with each other, and are pitted rugose for the cartilaginous articulation. 



Distal breadth, 

 Breadth at neck, 

 Diagonal across condyle. 

 Length, 



It is seen, therefore, that this bone is remarkably robust, much more so than in the Plesiosauri of adult age. 

 That the individual to which it pertained is not mature, appears from the dorsals accompanying, in which the neural 

 arch is not fully coossified to the centrum. We can regard the species as a robust and powerful animal, in which bulk 

 is more prominent than length. 



Anterior dorsal, length centrum, 



Width do., 



Depth do., 



Length articulation for neurapophysis, 



Width do. do., 



The centrum is much constricted medially and the diapophyses are given oft* from the neurapophyses, the lower 

 margin corresponding with that of the bottom of the neural canal. This specimen is from Barnesboro, and was 

 submitted to me by Prof. Cook, State Geologist. 



Locality: the Cretaceous Green Sand of New Jersey; upper bed. 



CIMOLIASATJRUS GRANDIS. 



Brimosaurus grandis, Leidy, Proceed. Ac. Nat. Sci., 1854, 72; tab. I., II. 



From Cretaceous of Clark County, Arkansas (near Greenville). 



I have not seen any part of this, the largest species. It is, from Leidy's figures and description, distinguished 

 by the relatively greater width and height of its vertebrae, and has been therefore a shorter and more massive animal 

 than its congeners. As nothing beyond Leidy's description is known of it, I append the latter. 



It was represented by vertebrae from near Greenville, Clark County, Arkansas. They had been kindly loaned by 

 W. T. Roberts, an agent of the Arkansas Mining Company, who had discovered them with numerous others. Dr. 

 L. stated that, in his visit to St. Louis, Mr. Alb. Koch, the industrious collector of fossil remains, had exhibited to 

 him a collection of bones from the same State, and apparently of the same animal, which he was on the eve of 

 sending to Berlin. The specimens are remarkable for the robust transverse processess, which project laterally 

 from the lower part of the body, and terminate in a large facet for the articulation of a rib. The bodies are 

 cylindroid, and are terminated by slightly concave or nearly flat articular surfaces. The sides of the body are moder- 

 ately concave, and have an acute margin at the articular surfaces. On each side of a median prominence of the under 

 side of the body a large vascular foramen exists. These vertebrae resemble those of Cimoliasaurus magaus from The 



In. 



Lin. 



2. 



5.1 



3. 



7. 



2. 



10. 



1. 



11. 



1. 



1. 



