From Henry's Fork.
Hadrianus octonarius, Cope.
Geol. Survey of Terrs., 1872. p 630.
Represented by the right humerus of a large individual.
This bone is intermediate in character between the corresponding bones of Testudo and Emys. The head is longer and narrower than in the former genus; it is implanted on a short, distinct neck, and is strongly convex in both directions. The articular surface extends to the base of the internal tuberosity. The tuberosities, especially the external one, are very large and thick. The external rises above the head, and resembles that of Emys in shape. The fossa separating the tuberosities is comparatively narrow. The shaft is much like that of Emys, but is somewhat more strongly curved; not so much, however, as in Testudo, and the distal end is not so much flattened. The anconeal fossa is wider and deeper than in either genus. The trochlea is broad, and divided by an obscure groove into a small and convex radial face, and a nearly plane (transversely) ulnar face. The condyles are prominent and rugose.
Found near Dry Creek.
EMYS.
Emys wyomingensis, Leidy.
Cont. to Ex. Vert. Fauna, p. 140.
Represented by six perfect shells from Cottonwood and Dry Creeks, and Henry's Fork, and a shoulder girdle from Cottonwood Creek, which is provisionally referred to this species.