ohyals (see fig. 5A) are preserved in
several specimens. These are long, curved bones with a posteroventral
process and widened, flaring posterior margin. The medial (?) surface is
concave in one specimen. The lateral (?) surface displays a distinct
ridge on several specimens, arising on the dorsal surface opposite the
posteroventral process and extending diagonally to the anteroventral end
of the anterior limb. The impression of one other specimen appears to
have a central ridge because of greater dorsal thickness and narrowness.
Both surfaces are unornamented.

The urohyal (see fig. 5B) is an unornamented, Y-shaped bone, with the
stem of the Y pointing anteriorly. Orientation with respect to dorsal
and ventral surfaces is uncertain. In one view a faint ridge, also
Y-shaped, occurs on the expanded posterior portion, and the surface is
convex. The anterior process has a convex surface, sloping evenly off to
the lateral margin; the opposite side of the process has a concave
surface. The posterior portion has a slightly depressed area (see fig.
5B) at the junction of the "arms" of the Y.

The five branchial arches are represented by the ceratobranchials,
several of which are preserved on K. U. no. 11431. These are long bones
with anteriorly curving ventral ends. The medial surfaces are partly
covered with minute granular teeth; only the dorsal part is without
teeth. The dorsal articular surface is convex dorsally and rounded.

The mandible (fig. 3), the best specimens of which are K. U. nos. 788
and 11425, is seen only in lateral and ventral views, with only angular,
splenial and dentary visible.

The angular forms the main body of the mandible, and is similar to that
of _Spermatodus_. The dorsal margin of the angular is expanded in the
central region, with some variation. One specimen has an expanded
portion slightly anterior to that of the opposite angular. The articular
surface near the posterior end has not been observed; the posterior end
of the angular slopes off abruptly. The anterior sutures are seen in
only two specimens, K. U. nos. 788, 11425. The dentary meets the angular
in a long oblique suture; the dentary gradually tapers posterodorsally
and ends on the dorsal surface of the angular. The splenial fits into a
posteriorly directed, deep V-shaped notch on the ventral surface. The
lateroventral surface of the angular contains sensory pores of the
mandibular line. The ventral surface extends medially into a n