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shelf, approximately 1.0 mm. wide, which extends the full length of the
bone; the external surface of this shelf is smooth and slightly concave
dorsally. Ornamentation of the angular consists of tubercles and
longitudinal or oblique striae, occurring mostly on the expanded
portion. The medial surface is not seen. Several broken specimens show
a central canal filled with a rod of calcite; in one of these the
sensory pores are also calcite-filled and appear to be connected to the
rod. Thus the pores originally opened into a central canal.

The dentary is an unornamented bone with the anterior half curving
medially; the greatest height is anterior. This bone in specimen K. U.
no. 11425 bears irregularly spaced, simple, recurved, conical teeth;
nine were counted, but there is space for many others. One other
specimen, no. 11429, seems to have tiny tubercles on the surface. The
dentary meets the splenial dorsally in a straight suture.

The splenial also curves medially, and as stated, meets the dentary in a
straight suture. Ornamentation on this bone was not observed. The
posterior margin is V-shaped and fits the notch in the angular. The
ventral surface bears three or more sensory pores of the mandibular
line.

The gular plates are oval. The medial margin is straight to slightly
curved, the lateral margin curved crescentically, the posterior end is
blunt, and the anterior end somewhat rounded. Ornamentation varies
greatly; some bones show only a few tubercles, whereas others exhibit an
almost concentric pattern of closely spaced striae. Typically there are
some tubercles in the anterior quarter or third of the total length;
these pass into longitudinally oriented striae in the posterior section.
A few have only randomly oriented, widely-spaced striae. The internal
surface is smooth.

The coronoid (K. U. no. 11428) is a triangular bone, with the apex
pointing dorsally. The lateral surface is smooth; no teeth were
observed. Moy-Thomas (1937:292, 293) mentions several tooth-bearing
coronoids in _Rhabdoderma_, but as yet these have not been seen in
_Synaptotylus_.

_Axial skeleton_

Only three specimens (K. U. nos. 786F, 787F, 11450) show parts of the
vertebral column, but isolated neural and haemal arches are numerous.
All are of the coelacanth type, having Y-shaped neural and haemal
arches, without centra. A total count of 38 was obtained, but this was
incomplete; the actual number was probably near 50. Counts