256 [October, 



5. Omosaurus perplexus, Leidy. 



An enaliosaurian, based upon a number of teeth of varied character, vertebrae, 

 fragments of ribs and other bones, and the impression of a dermal pLxte, obtained 

 from the coal field of Chatham Co., North Carolina, by Prof. Emmons and also 

 by Prof. M. Tuomey. 



Teeth elongated conical, pointed, nearly straight, or n:ore or less mo- 

 derately curved inwardly, with opposed carinte on the inner side, which 

 are entire or denticulated ; transverse section subcircular, flattened in- 

 ternally ; surfaces even, or more or less distinctly fluted on the outer side or all 

 around, and covered with minute interrupted ridges, which are vertical on the 

 even surface, oblique on the fluted surface, and divergent downward in the vi- 

 cinity of the carinas. Crown solid, enamel thin, dentine concentric ; fang sub- 

 cylindrical, hollowed at base. Length from 5 lines to 1^ inches, breadth from 

 2 lines to 4| lines. 



Bodies of the vertebrse bi-concave and much constricted, as m Palceosaw'us? 

 and Ch-jKysaunis. Length of one of the posterior cervical bodies 16 lines, 

 depth of its articular surfaces 17 lines, width 15 lines. 



Dermal plate covered with radiating, bifurcating and anastomosing ridges. 



Allied to Clepsysaurus and Centemodon, Lea, and probably identical with them. 



Labyrinthodonta. 



6. DicTYOCEPHALUS KLEGANS, Leidy. 



Founded on the upper portion of a cranium discovered by Prof. Emmons in 

 the coal-field of Chatham Co., N. C. Plates of the cranium covered with reti- 

 cular ridges in a general radiant manner. Parietals comparatively short, 

 broader in front than behind ; parietal foramen near the centre of the bones. 

 Occipitals quadrate, a little longer than broad. Posterior outline of the cranium 

 with a superficial transverse concavity on each side and not a deep sinus as in 

 Trematosaurus and Arcliegosmirus. Breadth of occipital outline 28 lines ; length 

 of parietals 8J- lines, breath anteriorly 3J lines, posteriorly 3 lines. Probable 

 length of head, considering it to have had nearly the proportions of Tremato- 

 saurus, 4 inches, breadth 2^- inches. 



Pisces. 



7. IscHTRHiZA AXTiQUA, Leidy. 



The genus was originally based on a tooth found in the Green Sand of New 

 Jersey. Two teeth aj^parently of a second speceis have been obtained by Prof. 

 Emmons on the Neuse River, N. C. 



Crown of the teeth, when perfect, apparently, laterally compressed conical. 

 Fang robust, quadrately pyramidal, curved ; with a rugged base which is bifur- 

 cated antero-posteriorly and more deeply before than behind. Pulp cavity en- 

 tirely closed at bottom. Probable length of specimens when entire IJ, and 2 

 inches; length of fang 10 lines, and 1 inch ; breadth of crown at base antero- 

 posteriorly 5 lines, 6 lines ; laterally 3| 1., 4|- 1. ; breath of fang at bottom an- 

 tero-posteriorly 7 1., 8^ 1.; laterally 6J 1 7 1. 



Notice of some Remains of Fishes discovered hy Dr. John E. Evans. 

 By Joseph Leidy, M. D. 



1. Clupea humilis, Leidy. 



Founded on an impression of the fish upon one half of a clay stone nodule 

 from a tertiary deposit of Green River, Missouri. ' 



Length 3^- inches; greatest depth 16 lines. Dorsal fin with 15 rays; abdo- 

 minal 7, anal 14; caudal 20? From the head to the position of the anus 28 

 abdominal spines may be counted. 



2. Cladocyclus? occidentalis, Leidy. 



Based on specimens of isolated scales, attached to masses of an ash-colored 

 chalk, from the cretaceous deposite of the upper Missouri. 



