28 WOODWARD : FOSSIL FISHES OF THE UPPKR LIAS OF WHITBY. 
contained about six times in the total length of the fish. The head 
is too imperfect for detailed description, but the mandible distinctly 
projects in front of the upper jaw, the maxilla exhibits its charac- 
teristically arched form, and the position of the eye is marked by a 
black stain. The width of the opercular apparatus seems to have 
equalled half the length of the cranium. The vertebrje are imperfect 
and partly disturbed, so that they cannot be counted ; but two centra 
in the abdominal region are shown as smooth constricted cylinders. 
The few remains of delicate ribs prove that they terminated not far 
from the ventral border ; the slightly stouter but nevertheless delicate 
neural and haemal arches m the caudal region are distinctly fused 
with their corresponding centra. The pectoral fin comprises not less 
than sixteen or eighteen delicate rays, of which the foremost is pre- 
served for a length equalling two-thirds the maximum depth of the 
trunk. The pelvic fins arise much nearer to the anal than to the 
pectorals, and that of the right side shows at least eight rays, the 
foremost only a little inferior in length to that of the pectorals. The 
dorsal fin arises immediately behind the pelvic pair at a point nearly 
midway between the occiput and the caudal fin ; it is somewhat 
deeper than long, while the length of its foremost ray is about equal 
to the depth of the trunk at its insertion. The smaller anal fin arises 
opposite the hinder end of the dorsal fin. The caudal fin is deeply 
cleft, depressed in the fossil, and partly destroyed by a vein of spar 
which crosses it. There is nothing worthy of note in the squamation, 
unless some small streaks above the vertebral column, especially in 
the caudal region, denote a large canal for the " lateral line." The 
second specimen (fig. 2) is larger and more imperfect than the first, 
preserved in soft shale and with the mouth widely open. It is 
essentially similar in all features which can be compared, and shows 
the same longitudinal indents or streaks in the scales above the 
vertebral column both in the abdominal and caudal regions. The 
dorsal fin is very imperfect, the anal seems to be a little displaced 
backwards, and the caudal is almost completely destroyed. The stain 
on the shale produced by the remains of the scales and soft parts, is 
probably deeper than the original depth of the trunk, as suggested 
by the obvious displacement of the dorsal, anal, and pelvic fins. 
