502 Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 
The spinal column consisted of thirty vertebre, and of these seventeen are 
caudal; they are slightly higher than broad. The column extends with a graceful 
curvature from the head to the tail. From each vertebra in the caudal region 
there extends a strong hemal and neural spine, gently curved backwards. The 
neural spines extend forward to the occipital region of the head; the neural ones 
are replaced by a series of ribs; the latter extend from the vertebra 0:4 of an 
inch, or two-thirds the depth of the abdominal cavity. Interspinous bones 
connect the hemal and neural spines with the base of the dorsal and anal fins. 
They are thin and slender, and twice the number of the spinous processes. 
The dorsal fin extends from a point midway between the snout and the tail, 
along the dorsal surface quite to the base of the tail. It is supported by numerous 
short rays, which become smaller posteriorly. The anal fin commences opposite 
the anterior rays of the dorsal one, and extends to the base of the caudal. As 
with the dorsal, the anterior rays are the stronger, and they decrease in size 
backwards. The caudal fin is supported by strong rays; it is moderately forked, 
and the external rays of the two lobes are supported by a series of rudimentary 
rays, firmly imbricated along its base. 
The pectoral fin is situated on the side of the fish, but low down towards the 
median line of the abdomen. It is composed of six or seven small rays, and was 
apparently of comparatively feeble dimensions. ‘The fin is connected with a long 
and comparatively small series of bones, forming the pectoral arch. The ventral 
fins are located on the abdominal surface, at a distance of 0-1 of an inch from and 
immediately below the pectorals. They are larger and stronger than the pectoral 
fins; the number of rays cannot be distinguished. 
The scales are thick, circular behind, with smooth margin and surface. Those 
on the dorsal surface are large, elongate, rugose, and have a pointed and imbri- 
cated appearance; they extend over the head to a position immediately above the 
orbit. ‘The scales on the ventral surface are also much elongated; the surface is 
rudely striated, and the abdominal extremity of the scale is quite pointed, 
producing a serrated appearance. 
Formation and Locality.—Soft chalk: Sahel Alma. 
Ex coll.—Lewis Collection, Mr. Robert Damon, Weymouth. 
Genus. Spathiurus.* Davis. 
Posterior part of fish only is preserved. The vertebral column is thick and 
strong; its caudal extremity is diverted upwards in a marked degree. The 
caudal fin is attached to the lower convex surface of the vertebrze by a series of 
long hemapophyses, rod-like at the base, but expanding to a spatulate form near 
* oraby, a paddle; ovpa, a tail. 
