106 THE WASATCH AND BEIDGER FAUN^. 



Dr. Lemoine has toimd this genus in the Suessonian formation near 

 Reims, France, and liis material has enabled him to furnish some characters 

 in addition to the above mentioned. He states* that the quadrate bone is 

 "non sonde," find that the limbs resemble both those of Crocodilia and 

 Lacertilia, and are apparently adapted to aquatic habits. 



Ignorance of the structure of the skull has prevented a definite conclu- 

 sion as to the true position of this genus and its allies. Dr. Leraoine's ob- 

 servation makes it appear that they belong to the Streptostylicate division, 

 and that they form an aberrant division of the LacerfiUa or Pythonomorpha. 

 For the present I refer them to the former, but they will constitute a dis- 

 tinct sub-order with the definition given on a preceding page. Besides 

 Champsosnurus, the Champsosaurklce include the genus Ischyrosaurus Cope, 

 which difiers from it in the heavy subfusiform ribs, and the flat articulation 

 between the centrum and neural arch of the vertebrae. 



This genus was named by Professor Gervais at nearly the same time 

 with myself His publication was made in the February no. of the Jour- 

 nal de Zoologie for 1877, and mine in the Proceedings of the Philadelphia 

 Academy for December, 1876. My description did not appear until Jan- 

 uary 10, 1877, and although I do not know of the precise date of the pub- 

 lication of the Journal de Zoologie, it was presumably not until some weeks 

 later. 



There have been four species of this genus described from the Ameri- 

 can Laramie formation, viz: the C. profundus, C. annectens, C.brevicollis, and 

 C. vaccinsulensis. The species from Reims is called C. lemoinei Gerv. I 

 distinguish three species from the Puerco bed of New Mexico, which dift'er 

 from the Laramie species in obvious ways. Vertebrae of a species from the 

 Laramie were figured without name by Leidy in the Transactions of the 

 American Philosoph. Society, 18G0. 



The Puerco species differ as follows: 

 Small; dorsal centra witli semicircular faces, much wider than' deep; an- 

 terior dorsal keeled below C. amtralis. 



Large; dorsals witii cordate faces aliti^le wider than deep; none known 



to be keeled below C. puereeitsit. 



Medium; length, width, and depth of dorsal centra equal; faces snb- - 



round ; not keeled below; axis not keeled below C. saponensis. 



"Coromnnication siir li-s Ossomcnts foagilcs desTerr. Tortiaires Iiifs. dc8. Euv. do Reims; Assoc. 

 Fran;, jioiir IWvanc't ilcs Soiriices, IH^O, p. 15. 



