The bones of the skull show the coarse sculpturing of the larger species of Microsauria. It consists more of radiating grooves than of pits. The skull, as restored ([462]), is broadly ovate, with the posterior border truncate. The muzzle is broad and the nostrils are, apparently, located near the anterior margin.
The posterior border of the orbits lies near the median transverse line of the skull. They are circular and are removed some distance from the margin of the cranium. Only the frontal and parietal can be determined with certainty.
The mandible is heavy and is provided with pleurodont, heterodont teeth. Near the anterior end of the mandible there is a very long fang-like tooth, longitudinally striated and slightly recurved, which arises from a broad base and attains to considerable prominence. The other teeth are smaller, though the next succeeding one is still of considerable size. All of the teeth preserved are longitudinally striated, but only the two anterior ones are recurved to any extent.
| Measurements of the Type. | |
| 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.