"The upper jaw is set with teeth which are more uniform in size and there is but little tendency to heterodonty. These teeth are also striated at their base and all end in a sharp point. They are all, apparently, straight. There is no tendency to curve as there is in the genus _Macrerpeton_. The upper teeth are more closely set than are those of the lower jaw, which are rather distantly placed. "Another specimen of a smaller individual presents the same portions of the skeleton and the same characters. It is possible that this skull will be found to belong to _Ichthycanthus ohiensis_ Cope, which is based on very large vertebræ and limb bones. The remains described as _Leptophractus lineolatus_ are, however, unlike any other skull remains which are thus far known. "This species represents one of the largest types of the Carboniferous Amphibia of Ohio. It probably attained a length of several feet. It was also the most carnivorous of any of the forms." Measurements of the Type Specimen of Leptophractus lineolatus Cope. mm. Length of specimen, as preserved 98 Depth of dentary bone at the middle 30 Anteroposterior diameter of mandibular tooth at base 3.5 Length of a posterior mandibular tooth 9 Length of longest tooth in jaw 22 Anteroposterior diameter of the same at base 6 Length of small maxillary tooth 7 Anteroposterior diameter of same at base 2 Collected by Dr. J. S. Newberry. Other specimens of the species are Nos. 1086 G and 1087 G, American Museum. =Eurythorax sublævis Cope.=[C] [Footnote C: Dr. Hussakof now regards (Bull. Amer. Mus. Nat. Hist., vol. 35, p. 128, 1916) the type specimen of this species as an opercular element of one of the dipnoan fishes [_Sagenodus sublævis_ (Cope)]. The discussion is left here, however, as a matter of historical interest.] Cope, Proc. Am. Phil. Soc., p. 177, 1871. Cope, Geol. Surv. Ohio, II, pt. II, p. 401, pl. xl, fig. 4, 1875. Type: Specimen No. 8605 G, American Museum of Natural History, Collection of Dr. J. S. Newberry. Horizon and locality: Linton, Ohio, Coal Measures. The genus and species were established on a single, large, almost perfect interclavicle of peculiar form. It may or may not be distinct, but it can not be associated definitely with any known genus, so that it will be designated as Cope described it. It exhibits on its outer or lateral borders broad, smooth surfaces for the contact of the overlapping margins of the lateral plates. The form is subround, with a large excavation from the posterior margin on each side. The narrowed portion left in the middle behind has a convex outline. Some delicate radiating grooves occur on the exposed surface, but they are very shallow. Measurements of Type.