52 



Field Columbian Museum — Geology, Vol. II. 



fore limb, is impossible to say— the only differences that could be 

 detected are the rather lighter weight or greater slenderness of those 

 located here. Their relations to each other are precisely those of the 

 fore limb. It seems probable that the fourth bone on the posterior 

 side of the first row, articulating with the femur, was wanting in life, 

 or at least was. very small — none were preserved. The fore and hind 

 limbs, as restored, are of the same length. All four paddles were 

 restored as completely as those shown in the figures. 



CIMOL1ASAURUS SNOW1I. 



Skull. — The skull of this species was briefly described by me in 

 the Transactions of the Kansas Academy of Science for 1890, to which 

 some additional observations were made by Cope in the Proceedings 

 of the. American Philosophical Society for 1894, p. 109. I give here 

 a more complete comparative description, in the light of the infor- 

 mation furnished by other known forms, especially DolicJiorJiynchops-. 



Fig.13. 



Skull of Cimoiiasaiirns siwivii Will. Pfn. premaxilla; en., external naris; mix., maxilla; ff. t 

 prefrontal; pof., postfronto orbital; J., jugal; sq.. squamosal; pa., parietal; so., supraoccipital; co., 

 exoccipital; q.. quadrate; qj. quadratojugal; d, dentary; sur., surangular; ang., angular. 



The parietals form a steep, roof-like covering, ascending into a 

 thin, sharp, sagittal crest, extending through nearly their whole 

 length, from the attachment of the squamosals posteriorly as far for- 

 ward as the posterior part of the orbit. This crest, throughout most 

 of its extent, forms a thin, vertical plate, with nearly parallel sides 



