AND AVES OF NORTH AMERICA. 



227 



wards, the outer is horizontal, and corresponds to the prominent ridge in front of the meatus. The ridge connecting 

 the anterior lamina with the condyle, is strongly convex and ridged or crenate round the external margin. The ridge 

 bounding the meatus in front is concave. The condyle is much wider and more convex intero-anteriorly; the remain- 

 ing portion is narrowed. There is a deep superficial pit just above the meatus. The anterior semi-circular expansion 

 is shallow concave on the Inner side. 



The form of this element indicates a nearer relation of Clidastes to Liodon validus than to Mosasaurus. 



The type specimen of this species was found in the bed of a small stream, where it had fallen from its original 

 position in the bank. 



Rotten Sandstone of the upper Cretaceous of Alabama. Dr. E. R. Showalter. 



OPHIDIA. 



PAL^OPHIS, Owen, 



PAL.EOPHIS LITTORALIS, Cope. 



Proceed. Acad. N. 8oi., Phil., 1888, 2114. Dinophis Uttoralis, Marsh, Am. Journ. Bci. Arts, I860, p. 400. 



This is the first serpent whoso remains have been found in the United States, in deposits older than the postplio- 

 cene. We owe its preservation to D. Knieskern, of Shark River, New Jersey, best known by his botanical investiga- 

 tions. Itis in possession of the New Jersey State Geological Survey, and has been submitted to me by Prof. (in.. II. 

 Cook, the Director, for examination. The specimens consist of three vertebra;, neither of them perfect, the most so 

 with neural aroh, but with diapophyses broken off. 



The more perfect is an anterior dorsal, with two hypapophyses, the anterior small and directed forwards, the pos- 

 terior larger, and directed vertically downwards. The ball has a considerable superior up-look, though the groove 

 which bounds it is but little oblique. Centrum much compressed behind the middle. Plane of basis of zygapophysis 

 opposite floor of neural arch; zygapophysis directed slightly upwards and outwards, continuous by a broad wing run- 

 ning posteriorly, with the diapophysis. Neural arch well elevated, broken oil' behind. The basis of the neural spine 

 is narrow on the anterior part of the arch, and docs not reach the anterior margin. 



Lines. 

 Length centrum (ball to edge cup), 8.25 



Depth ball, 4.25 



Width " 5. 



" between extremities of zygapophyses, 8. 



Depth cup and neural arch, 7.5 



Width neural arch behind, 2.25 



A strong ridge extends from the zygapophysis posteriorly parallel with the centrum. There is no ridge continued 

 from the zygosphen, exoept a slight ridge below the fossa, which is above and back of the diapophysis, the surfaoe of 

 the vertebra is smooth. 



Another vertebra is rather broader in proportion to its length, and less compressed. 



Length (as above), 7.H 



Width ball, 5, 



In both, the bail has a sub -triangular outline. In the more perfect, the base of the neural canal is divided by a 



narrow longitudinal epapophysis. 



Locality. The Eocene Green Sand Bed of Squankum, Monmouth Co., N. J. 



PAL^EOPHIS HALIDANUS, Cope. 



Proceed. Acad. Nat. Bci., 1808, 235. Dinophis halidanui, Marsh, 1. o. 1869, 400. 



A single vertebra represents this species. It indicates one of the largest of the genus, being little different from 

 the P. typhmtlB of Owen, in size. The bulk of the vertebra, is double that of the P. liltoralis. In addition to this 



