The fore limb is represented by the upper portions of the ulna and radius and 2 digits of the right hand. The digits are long and slender and seem to represent digits I and II, since they show evidences of 3 and 4 phalanges respectively. The portions of the forearm preserved are too meager for description. The vertebræ have already been characterized as of the type first described in Urocordylus. The neural fans are not much, if any, wider than the hæmal fans. They are both situated on an elongate spine with a slender base. The edges of the two fans are pectinated and the dorsal spine is distinguished by the presence of a longitudinal groove in the center of the spine. The length of the tail may have been considerable, judging from the character of the vertebræ preserved Measurements. mm. Length of specimen 150 Width of belly, maximum 28 Length of lateral chevron plate 7 Width of lateral chevron plate 1.75 Length from tip of lateral chevron to median angle 10 Length of a caudal vertebra 10 Width of the same vertebra with spines 20 Height of neural spine 8 Height of hæmal spine 8 Width at distal end of hæmal spine 3 Width at distal end of neural spine 3.5 Length of foot, as preserved 12 =Genus LEPTOPHRACTUS Cope, 1873.= Cope, Proc. Phila. Acad. Nat. Sci., p. 340, 1873. Cope, Geol. Surv. Ohio, II, pt. II, p. 399, 1875. Cope, Proc. Am. Phil. Soc., XX, p. 461, 1882. Type: _Leptophractus obsoletus_ Cope. The genus was established on various parts of the cranium of a large amphibian. The only parts which can with certainty be referred to the genus are the upper and lower jaws of 3 specimens. These bear large teeth, round in section at the base, but with acute compressed apex, with a cutting-edge on the anterior face; the enamel is delicately grooved, as an external indication of the labyrinthic structure. A characteristic feature is seen in the presence of a large elongate tooth in the upper jaw, in the position of a canine which much exceeds in length any of the others. The sculpture of the cranium is but little marked in the known specimens. In the type the lower jaw is marked with inosculating grooves. Three species are known, which are among the largest of the Linton Amphibia. =Leptophractus obsoletus Cope.= Cope, Proc. Phila. Acad. Nat. Sci., p. 340, 1873. Cope, Geol. Surv. Ohio, II, pt. II, p. 399, 1875. Cope, Proc. Am. Phil. Soc., XX, p. 461, 1882. Type: Specimen Nos. 55 G and 57 G, American Museum of Natural History. Horizon and locality: Linton, Ohio, Coal Measures.