Body covered with scales; head naked; margin of upper jaw formed by the premaxillaries; mouth toothless. Pharyngeal teeth in a single series, and exceedingly numerous and closely set. Dorsal fin elongate and opposite the ventrals. Anal short, or of moderate length.
AMYZON, Cope.
U. S. Geolog. Survey of the Terrs., 1872, p. 642.
Allied to Bubalichthys. Dorsal fin elongate, with a few fulcral spines in front. There are three broad branchiostegals. The vertebræ are short, and the hæmal spines of the caudal fin are distinct and rather narrow. The teeth are arranged comb-like, are truncate, and number from thirty to forty. The dentary bone is slender and toothless, and the angular is distinct.
Amyzon commune, Cope.
U. S. Geolog. Survey of Terrs., 1873, p.
Represented by several fine specimens from near Castello's Ranch, Col.
SAURODONTIDÆ.
For a very complete definition of this family, see Cope's Cretac. Vert., p. 183.
PORTHEUS, Cope.