O34 Davis——On the Fossil Fishes of the Chalk of Mount Lebanon. 
: Pycnosterin niger, Prcrer et HumBeErt. 
Beryx niger. Costa, O. G., 1855. ‘* Descrizione di alcuni pesci fossili del 
Libano,” p. 4, pl. u., fig. 1. 
Pycnosterinx niger. Prcrer et Humpert, 1866. ‘Nouv. rech. sur les poiss. foss. 
du M. Liban.,” p. 43. 
MM. Pictet and Humbert observe that there can be no doubt that the 
fossil fish figured by M. Costa, under the name of Beryx niger, belongs to the 
genus Pycnosterinx. It is related to P. dorsalis, Pictet, from which it differs 
by the dorsal fin being smaller and shorter. It approaches still more to P. 
russeggeril, Heckel, and it may be not impossible that it will be found necessary 
to unite the two. 
Lormation and Locality.—Soft chalk: Sahel Alma, Mount Lebanon. 
Pycnosterine latus, Davis. 
(Pl. xxvit., fig. 2.) 
This specimen differs from those already described in the peculiar height 
of the body as compared with its length. The specimen is the largest I have 
seen of the genus. Its head has been disturbed and the component bones 
displaced ; but the remainder of the body appears to be in its normal position. 
The length of the body between the posterior margin of the operculum and 
the base of the tail is 1°8 inches, and the height of the body, exclusive of the 
dorsal and anal fins, is 3°2 inches; the height of the peduncle of the tail is 
08 inch, and the length of the tail at least an inch. 
The head was probably an inch and a quarter to an inch and a half in 
length. The orbit was large, and situated near the superior margin of the 
head; the jaws and teeth cannot be separately distinguished ; the opercular bones 
moderate in size. The operculum is 1:0 inch in length and 0:5 inch broad, 
strong and straight or slightly concave in front, convex behind; the sub-operculum 
is similar in form but more elongated. The tympanic or pterygoid bones are 
largely developed and occupy a large area between the orbit and the maxillary 
bones. 
The spinal column is straight, except a distinct curvature upwards of the 
terminal three or four vertebra supporting the caudal fin. It is composed of 
twenty-eight vertebra, of which eighteen are caudal. The vertebre are 0:15 
inch in height, and their length is equal to half the height. The hemal and 
neural apophyses are long and slender. ‘The interhemal and interneural spines 
are more numerous than the hemal and neural spines which support them, 
and are attached to the rays of the dorsal and anal fins by a broad expansion 
of théir extremities. The ribs are about an inch in length, small, slender, and 
curved backwards, | 
