528 Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 
uncommon one during the deposition of the Sahel Alma chalk beds. The length 
of the body is about 4:0 inches; of this the head occupies one-fourth. The 
height of the latter is little more than half its length; attenuated in front. The 
jaws are straight, and are furnished with small, conical, pointed teeth, more or 
less arched and unequal, and not very numerous. The orbit is large, and superior 
in position. The operculum slightly pointed behind, and longer than broad. 
The branchiostegal rays are long and arched, and apparently five in number.. 
The spinal column is somewhat feeble, the vertebrae short and contracted 
medially. M. Pictet estimates the number at sixty, but this is probably too 
large. Neurapophyses extend from the dorsal surface of each vertebra, and 
they in turn support interneural spines, to which are attached the rays of the 
dorsal fin. Hzemapophyses are attached to the lower surface of the vertebree 
and support the interhemal spines. The ribs are fine and slender. 
The dorsal fins are large, with a basal extent of about 1:0 inch. The 
anterior rays are inserted immediately behind the occiput; they are eighteen 
in number, long, and more or less slender. M. Pictet states the number of rays 
in the dorsal fin are fifteen, attaining a length of 1:7 inch; this was, no doubt, 
due to the imperfection of his specimen. ‘The anal fin extends forwards from 
the base of the tail to a distance of 1:1 inch; its rays are short, but numerous, 
and, as already stated, are supported by interhemal spines. The caudal fin is 
moderately large, about an inch in length, and deeply lobate. 
The pectoral fins are attached to the side of the body; they are large, but 
not so large as the ventrals. In all the specimens examined the rays are more 
or less aggregated into a close mass, so that their number cannot be ascertained. 
The ventral fins are attached to the abdominal surface, beneath the position 
of the pectorals. Seventeen long and bifurcating rays 2-0 inches in length form 
the posterior and principal part of the fin; in addition there are five or six 
short rays attached to and constituting the anterior part of the fin, There is 
no evidence of scales. 
Formation and Locality.—Upper Cretaceous: Sahel Alma, Mount Lebanon. 
£x coll—tLewis Collection and Enniskillen Collection, British Museum (Natural 
History Department), London. 
Cheirothrix lewisii, Davis. 
D) ad 
(Pl. xxvi., fig. 2.) 
This magnificent example, which I have selected from a number of others 
in the National Collection, was obtained by Professor Lewis during his residence 
at Beyrout. For the most part it is wonderfully well preserved; a portion of 
the dorsal fin and the base of the tail have been carried away by the opposing 
