516 Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 
space between the two lobes. The rays dichotomize repeatedly, and they are 
jointed at short intervals. A series of imbricating rudimentary rays support each 
lobe of the fin. 
The pectoral fin is situated midway between the line of the vertebral column 
and the abdominal surface. It consists of about fourteen small rays, 0°7 inch 
in length, and is supported from the median portion of the pectoral arch. 
The ventral fin is attached to a process from the pectoral arch, and is inserted 
immediately under the base of the pectoral fin, on the abdominal surface. The 
ventral is much larger than the pectoral, its rays extending more than an inch in 
length. Like the rays of the unpaired fins, those of the ventral and pectoral fins 
are divided by dichotomization and are jointed. 
The scales are large; the exposed surface is 0°25 inch in height; the posterior 
margin circular and deeply denticulated. In the highest part of the body there 
are twelve scales in a vertical series; nearer the tail the number is reduced to 
eight. Along the lateral line the number is twenty-five, between the posterior 
margin of the operculum and the tail. On the dorsal surface of the body the 
number will be greater, on account of the extension of the scaly covering to the 
upper surface of the cranium. 
This species is distinguished from Hoplopteryx (Beryx) syriacus, P. and H., 
by its graceful outline and more elongated form. The number of vertebre 
constituting the spinal column is larger. Its principal characteristic is in the 
relative position of the several fins. In H. syriacus the dorsal and anal fins are 
opposed, the ventrals considerably in advance of either. In the species now 
described, the anterior rays of the dorsal fin extend further forwards than those of 
the ventral, and the anal fin commences opposite to the posterior rays of the 
dorsal. 
Formation and Locality.—Upper Cretaceous: Sahel Alma, Mount Lebanon. 
Ex coll_—Lewis Collection; Robert Damon, Esq., Weymouth. 
Hoplopteryx spinosus, Davis. 
(Pl. xxvuu., fig. 1.) 
The body of this peculiar fish is 5 inches in length and 1°7 inch in height. 
The tail is 1°5 inch in length, making a total length of 6°5 inches. The form of 
the body is an elongated and flattened oval, or an oblong with rounded corners. 
The peduncle of the tail is small, 0°3 inch across. The anterior portion of the 
head is badly preserved ; otherwise the example is in fine state. 
The jaws and snout of the head are absent. The orbit occupied a median 
position, apparently between the extremity of the gill covers and the snout, and 
