The species was about as large as an adult Florida alligator, and probably exceeded or at least equaled in size any of the Carboniferous Amphibia. The following account is taken directly from Professor Cope's "Batrachia of the Ohio Coal Measures" (123). The description has been verified from an examination of the type material. "The teeth are rather distantly grooved for some distance above the base. They are of different sizes; the smaller are compressed, and with fore and aft cutting edges. The external surface of the dentary bone is marked with short oblique grooves along its middle region; above these are grooves which inosculate, forming a figure like an open net dragged in the long direction. "Excepting the grooves the teeth are smooth. The smaller ones are close together and their crowns are curved backwards; the larger ones are at more remote intervals; both have enlarged bases. Whether both forms are in the same series I can not determine. There are from four to five of the smaller to an inch. Measurements of Type of Leptophractus obsoletus Cope. mm. Depth of fragment of jaw 75 Length of smaller teeth 19 Length of longer tooth 23 Width of vertex at middle scuta 176 Width of paired median scuta 56 Width of single scute 36 Length of single scute 48 "Some vertebræ were found at the same locality, but there is no evidence as to the species to which they may have pertained. They are short, concave on one end, and probably so on the other. The centrum of one is 12 mm. in diameter; neural spines injured." (Geol. Surv. Ohio, II, pt. II, pl. 39, fig. 3.)