414 [October, 



Indications of five sp ties, with two neio genera, of extinct Fishes. 



By Joseph Leidy, M. D. 



1. Sicarius extinctus, Leidy. A species of a new genus, most probably of 

 fishes, but it may be of reptiles. It is founded upon the specimen of a tooth, or 

 it may be a scale or a spine ; and it consists of two portions. The body has 

 much the form of the scales of the Manis, but is surrounded at base with a thick 

 collar marked with close parallel ridges. The breadth of the body in its perfect 

 condition has been 15 lines ; its depth on the convex side 9 lines, and on the 

 vertical slightly concave side 11 lines. The root is 10J lines in breadth and 

 narrow towards the extremity, which is broken off, and it measures on one side 

 6 lines and on the other 4} lines in length. 



The specimen was obtained from a black stratum, belonging to the coal series, 

 in number 13 of Rogers, at the head of inclined plane No. 3, of the old portage 

 portion of the Pennsylvania Railroad. It was presented by Townsend Ward, 

 E3q., to Charles A. Poulson, Esq., from whom Mr. Conrad borrowed it for my 

 inspection. 



2. Edestus vorax, Leidy. A species of a new genus of fishes, founded on 

 the fragment of a jaw with portions of four teeth. The fragment of jaw is 3 

 inches in breadth by 10 lines in thickness at the dental border, and nearly double 

 that thickness at the opposed border, which is convex. It is composed of four 

 wedge-like segments excavated at base, so that those posteriorly are inserted into 

 those anteriorly, and each has a tooth coossified at the narrower border in^the 

 same plane as the broad surfaces of the specimen. The teeth resemble those of 

 Charcharodon, and in their perfect condition have been about 2 inches long, and 

 have had nearly the same breadth at base. They have strongly and coarsely 

 dentated borders, and are thinly coated with enamel. 



In relation to the affinities of the singular fish to which the fragment belonged 

 and its exact position in the skullf T suspect it to have been a portion of the upper 

 jaw of a genus allied to Lepidosteus, from the circumstance that the latter, in like 

 manner, has the upper jaw composed of a number of distinct segments. 



The specimen is most probably from the carboniferous series, and it was ob- 

 tained by "William S. Vaux, Esq., from an itinerant showman, who found it at 

 Frozen Rock, Arkansas River, 20 miles below Fort Gibson, in the Indian Terri- 

 tory. 



3. Oracanthus vetustus, Leidy. This species is founded on an ichthyodorulite, 

 the body of which in its perfect condition has been about 6 inches in length, and 

 it measures 1\ inches in breadth at base. The broad surfaces and slightly con- 

 cave border are thickly covered with mamillary tubercles arranged in very 

 irregular, transverse rows, and unsymmetrically on the two broad sides. 



The specimen is from Missouri Territory, and formerly belonged to Mr. Conrad's 

 collection now in possession of this Academy. Adhering to its base there is a 

 portion of black shale with a partially imbedded segment of an encrenite stem, 

 which Mr. Conrad considers as fixing the specimen in the carboniferous series. 



4. Pristis curvidens, Leidy. This species is based on a single tooth 5 inches 

 long by 8 lines wide at the point of exsertion. The posterior border at its 

 thickest part is 4J lines, is straight throughout, and only at its outer two-fifths 

 is slightly depressed. The anterior border is convex ; and the tooth is con- 

 siderably curved downward. 



The specimen was discovered by W. Taylor, Esq., in the Green Sand, near 

 Pemberton, New Jersey. 



5. Pristis ensidens, Leidy. This species is founded on numerous specimens 

 of teeth, of which the largest in their perfect condition have been about 1^ 

 inches long by 7 \ lines broad at base. They are straight and have both borders 

 equally acute and convex. 



The specimens were discovered by Capt. Bowman, U. S. A., in the sands of 

 Ashley River, South Carolina. 



Mr. Ilene La Roche Jr., and Dr. Samuel Lewis, of Philadelphia, were 

 elected Members. 



