Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 479 
The spinal column comprises fifty vertebrz to the base of the second dorsal 
fin, and beyond this ten or twelve others are preserved. The vertebre are 0-2 
to 0°25 of an inch in length; the diameter of the articulating surfaces being 
equal to the length; the central portion is extremely contracted, the osseous 
matter being small, whilst the cartilaginous greatly preponderated. 
The head, as already observed, is not well preserved anteriorly, and it 
cannot be exactly stated how far the snout extended beyond the mouth. The 
part preserved is 1:4 inches. The mouth extends 1'1 inch posteriorly, and the 
proximal termination of the jaws is 1 inch wide. The teeth vary in size: those 
of the lower jaw are broad at the base, culminating in a somewhat obtuse 
point ; those of the upper jaw are narrower, with longer and more lanceolate 
points; only one cusp extends from the base of each tooth. 
Of the unpaired fins the only one present is the second dorsal. Its base 
is 11 inches behind the anterior portion of the buccal orifice. Its anterior 
margin is armed with a spine 0°6 of an inch in length, of which 0°4 of an inch 
is enveloped in the integument of the fin, the remaining 0-2 of an inch is 
compressed laterally with a blunt and rounded extremity. The margin of 
the fin extends beyond the termination of the spine. 
The pectoral fins are large; the anterior margin is 3°5 inches behind the 
mouth, and extends 2°8 inches from the body; its base is 2:2 inches in length; 
the whole thickly coated with dermal ossicles, large and thick anteriorly, 
but smaller near the distal margin of the fin and posteriorly. 
It is probable that if the anterior dorsal fin had been exposed it would 
have had a similar spine attached as that of the posterior one which is exhibited. 
I am indebted to Mr. Wm. Davies, of the British Museum, for directing my 
attention to a paper by Herr. C. Hassé (‘‘ Einige seltene palzontologische 
Funde,” 1884), in which it is pointed out that the microscopical structure of 
the vertebre separates this fish from the genus Spinax and its closely related 
allies, Centroscyllium and Centrina, and shows its relationship to Centrophorus 
and Acanthias; from the latter it is separated by the character of its teeth, 
which much resemble those of some of the former genus; the embedded character 
of its short spine also closely resembles that of the existing Centrophorus. 
I therefore propose to indicate its relationship to that genus with the distinctive 
appellation, Centrophoroides latidens. 
Formation and Locality.—Upper Cretaceous: Sahel Alma, Mount Lebanon. 
£x coll,—Enniskillen Collection, British Museum. 
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