Page:Synopsis of the Exinct Batrachia and Reptilia of North America. Part 1..pdf/44

40 articular face is a oval. The size of the animal is similar to that of the Plesiosauri of medium dimensions, perhaps ten feet in length, admitting elongate neck and tail, of which there is no evidence.

Position.-Bed Q. Hayden's Section of Great  of. (Trans. Am. Philos. Soc., 1860, 135.) perhaps of the Cretaceous age; from the.

I refer the following species to this genus provisionally, and with doubt.

This reptile is represented by but few remains, which are in the private collection of Dr. Samuel Lockwood, of Monmouth County, N. J. A single dorsal vertebra, which he kindly lent me for description, presents characters which are so marked when compared with other marine Sauria as to require notice.

The centrum is of the general form of Plesiosaurus and, and the arch has a sutural attachment as in the former. The suture is the surface of a sub-round pit, almost like that of, and not like that typical of Plesiosaurus, or the young of CimaliosaurusCimoliasaurus [sic] magnus. In the latter the suture is an oval concavity which extends throughout the length of the centrum. The pit in this species measures little more than one-third the length of the centrum. The floor of the is quite flat. The sides of the centrum are strongly and regularly concave, rather less strongly below than laterally. The  regularly, and are not   or  as in many species. There is a strong venous foramen a short distance below the and two  below.

The species is further characterized by the regularly concave articular faces, without median plane or prominent portion, as in Cimoliosaurus species. They are more concave than those of the Elasmosauri also. The form of the surface is entirely circular.

This species I have dedicated to its discoverer, Dr. Lockwood, who has contributed in various ways to the progress of Natural Science.

It is the earliest sea saurian from this country, as it was derived from the clays which underlie the lower green sand bed. It was dug from a brick clay pit near Matteawan, Monmouth County, N. J.

Cimoliasaurus and , Leidy. Proceed. Academy Nat. Sei., Phila., 1851, 325-1854, 72, tab. ii, figs. 4, 5, 6, and 1851, 326; Cretaceous Reptiles, 22 and 25, tabs. IV., V., VI.  Leidy, Pr. A. N. Sci., Phila., 1855, 472.

This genus has been chiefly illustrated by Leidy, who has described remains of its species from the cretaceous deposits of many of the States east of the Mississippi. It has remained for the discovery of to prove that the two supposed genera named by Leidy, are really one, his supposed caudals of Discosaurus being really caudals of Cim-