AND AVES OF NORTH AMERICA. 55 



verse of those ordinarily observed among reptiles, whence I was induced to consider it as the type of a peculiar 

 group of high rank. This new is, of course, abandoned on a correct interpretation of the extremities. Leidy 

 detected the error in this arrangement, and the correction extends to Cimoliasauras as well. 



ELASMOSAURTJS ORIENTALIS, Cope. 



This species is indicated by two vertebra?. The first resembles both the twelfth from the first dorsal of the cervi- 

 cal series of Cimoliasaurus magnus, or the fifth from behind, of the same of Elasmosaurus. Its large size, lateral 

 longitudinal angle and small neural canal refer it with more probability to the latter genus. It appears to belong to 

 a species possessing some of the peculiarities of the Cimoliasaurus magnus, having the quadrate form of the median 

 cervicals of that animal, and lacking entirely the compression of the centrum and lateral concavity of the E. platyurus. 

 The parapophyses are stronger and slightly more descending than in the fifth cervical of the latter, again resembling 

 the more posterior vertebra of C. magnus Leidy. The bases of the parapophyses are more elongate than in the cor- 

 responding vertebra of C. magnus; the process was directed downwards at an angle of 45°, from the plane of the in- 

 ferior aspect. The inferior plane is slightly concave, with two venous foramina, each in a strong groove on each side 

 of a narrow median rib. The lateral surface is nearly vertical and slightly concave to the strong longitudinal angle. 

 Above the latter the face is oblique concave for a width equal to that below. The articular faces are transverse ovals 

 and slightly concave; their margin not prominent, nor ribbed on the lateral faces. 



Lines. 

 Length, 45 



"Width, 52 



Depth to canal, 36 



Lines. 

 Width canal, 7.7 



Length basis of parapophysis, 25. 



If we estimate this vertebra by the position of the lateral ridge to be about the eighth anterior to the last rib- 

 bearing, which I call cervicals in this genus, the transverse diameter of this vertebra in C. magnus is 

 two-thirds that of a dorsal with diapophyses near the middle of the centrum. Should the proportions have been 

 similar in this species, the diameter of that dorsal would measure 6j inches, indicative of the largest of American 

 saurians. As, however, in the genus Elasmosaurus the disproportion between the sizes of the caudals and the dorsals 

 is less than its ally, the latter have probably presented a diameter more like the same in E. platyurus. 



A second vertebra from near the same part of the column of a much larger individual was obtained by Dr. Samuel 

 Lockwood, superintendent of schools of Monmouth County, N. J., from Win. Conovers' pit in the lower bed, near 

 Marlboro, in that county. The diapophyses are directed downwards at an angle of 45°. The margins of the articular 

 faces are not everted, while the inferior presents an open emargination medially. The two inferior foramina are very 

 large. The measurements are as follows: 



Width of articular surface, 

 Depth do. do., 



Length centrum, 



The name is not given under any supposition of restricted habitat, which may have been similar to that of the 

 E. platyurus, but in view of the probability of its greater abundance where its remains have been found than 

 elsewhere. 



Our knowledge of this species is unfortunately confined to the two vertebras above described. The first is 

 from the lower cretaceous greensand bed, from near Swedesboro, Gloucester Comity, New Jersey. It was found in a 

 tailor's shop used as a block to secure a door. 



In. 



Lin. 



5 



9 



4 



3 



4 



6 



