mm. Length of the skull in median line 75 Width of skull at posterior border, estimated 80 Width of skull across orbits 60 Width of orbit 10.6 Length of orbit 12 Interorbital space 16 Length of jaw, as preserved 48 Width of jaw, maximum 16 Width of jaw, minimum 5 Length of largest tooth 11 Width of longest tooth at base 4.5 Length of shortest tooth 3 Width of shortest tooth at base 1 =Sauropleura foveata Cope.= Cope, Trans. Am. Phil. Soc., XIV, p. 24, 1869. Cope, Geol. Surv. Ohio, II, pt. II, p. 406, pl. xxxvi, fig. I, 1875. Type: Specimen No. 8676 G and obverse No. 8675 G, American Museum of Natural History. Horizon and locality: Linton, Ohio, Coal Measures. This species is represented by an interclavicle and its impression, which show a beautiful sculpturing entirely distinct from that of the other species of this genus. In size it is intermediate between the largest of the interclavicles of _S. scutellata_ and _S. pauciradiata_. The pattern of the sculpturing is, however, its main distinction. The plate is finely pitted and there are few evidences of grooves. Near the posterior border of the plate the pits become somewhat defined by ridges which take on a radiating pattern with the center of the plate as the center. The beveled margins are rugose, except at the edges. Measurements of the Type Specimen of Sauropleura foveata Cope. mm. Median length of interclavicle 43 Width of interclavicle, maximum 23 =Sauropleura enchodus Cope.= Cope, Proc. Am. Phil. Soc., p. 406, 1885 (_Anisodexis_). Type: Specimen No. (51) 2558, American Museum of Natural History, Newberry Collection. Horizon and locality: Discovered by Sam Huston at the Linton, Ohio, Coal Measures. An examination of the type specimen (plate 16, fig. 4) of this form resulted in no new facts. The reference of the species to the Permian genus _Anisodexis_ by Cope is probably incorrect. Our knowledge of the two known species of this genus is not sufficient to separate them, but for the sake of convenience the Linton species is placed in the genus _Sauropleura_. It is located here principally on account of the form and structure of the teeth. Cope's original description is given below: