482 Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 
(B)—BATOIDEI—RAYS. 
F amily. RHINOBATIDZ. 
Genus. Rhinobatus. BuLocu. 
Cranial cartilage produced into a long rostral process, the space between the 
process and the pectoral fins being filled by a membrane. Teeth obtuse, with 
an indistinct transverse ridge. Dorsal fins, two in number, without spines, both 
at a distance behind the ventrals. Caudal fin without lower lobe. Disk dilated, 
the rayed portion of the pectoral fins not continued to the snout. 
Rhinobatus maronita, Picret and Humperrt. 
Rhinobatus maronita, P. and H., 1866. ‘‘ Nouv. Rech. s. les Poissons foss. du 
Mt. Liban.,” p. 113, pl. xrx. 
Rhinobatus maronita, Fraas, Oscar, 1878. ‘Aus dem Orient. II. Theil. 
Geologische beobachtungen am Libanon,” p. 92. 
Rhinobatus grandis, Davis. 
(Pl. -xvis, fig: 4) 
The specimen of which the following description is given is large; the 
ventral surface is exposed ; the head and one side of the body are well preserved, 
the opposite side and the tail are wanting. The part of the specimen 
preserved is 21 inches in length; the head, between the snout and the pectoral 
arch, occupies 8°5 inches; from the pectoral to the pelvic arch is 5 inches, and 
the pelvic arch to its posterior termination takes 4 inches; the remaining 3°5 
inches are not very well defined, but may be the base of the tail. The vertebral 
column extends along the central axis of the fish. From the vertebrae to the 
outer margin of the head is 4:25 inches, giving a total breadth of 8-50 inches. 
Midway between the pectoral and pelvic arches the body is 10 inches across, 
5 inches on each side the vertebral axis. The fins are, unfortunately, to a 
great extent hidden beneath the matrix, but sufficient is exposed of the basal 
portions of them to indicate their nature. The whole surface of the fish was 
protected by innumerable minute dermal ossicles, flat and enamelled on the 
surface; beneath these was extended a thick layer of chondroid cartilage, filled 
with distinctly perceptible rounded ossifications, largest and thickest in the 
region of the head. 
