Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 535 
The dorsal fin in this specimen is not perfect, the anterior rays have 
disappeared, and the number of spinous rays cannot be ascertained ; there are 
eighteen or twenty soft rays partially preserved. The anal fin occupies a more 
posterior position than the dorsal, the insertion of its anterior rays being half 
an inch behind that of the dorsal; it is composed of four spinous rays and 
twenty articulated ones; the latter dichotomize. The spinous rays increase 
rapidly in length from the first to the fourth, the latter being 0°8 inch in length; 
the remainder of the fin-rays decreases in length backwards. The caudal fin 
is moderately large, with a broad base. The upper lobe is supported by ten 
and the lower one by thirteen rays; the basal portion, about one-fourth of an 
inch in length, is simple and undivided, beyond the rays are articulated and 
bifureate. The external rays of each lobe are supported by rudimentary rays. 
The pectoral fin is small, separated 0-5 of an inch from the abdominal margin 
of the body ; it is attached to the bones of the pectoral arch, the latter elongated 
and slender. It is composed of fourteen rays, which are only partially preserved ; 
the distal extremities are broken off. The ventral fins are imperfectly pre- 
served; the rays are strong, the anterior one or two spinous; the full number 
is not apparent ; they are attached to pubic bones immediately below the pectoral 
fins on the abdominal surface. The scales are small, circular, smooth on the 
surface, thick, with the posterior margin denticulated; they extend to and cover 
the base of each of the unpaired fins. 
It is proposed to designate this species by the name Pycnosterinx latus, 
indicating its great depth in proportion to its length. Its nearest relationship is 
with P. discoides, Heckel, and P. heckelii, Pictet; it differs from both in the greater 
depth of its body, in the number of its vertebra, and the character of its fins. 
The posterior position of the anal fin, as compared with the dorsal, distinguishes 
it from P. discoides, and the proportion and size of those fins separate it from 
P. heckelii; the latter is stated by Pictet and Humbert to possess eighteen rays 
in the dorsal fin and twelve in the anal; but in a very well-preserved specimen 
before me there are only sixteen rays observable in the dorsal and eleven in the 
anal. The caudal fin also distinguishes this species, consisting of thirteen rays; 
that of P. discoides has eighteen, whilst P. heckelii has sixteen rays. 
Formation and Locality—Upper Cretaceous: Sahel Alma, Mount Lebanon. 
£x coll.—R. Damon, Esq., Weymouth. 
Pycnostering lewisii, Davis. 
(PE xxvir., fic; 5.) 
This unique specimen is unfortunately slightly imperfect; the greater part of 
the head is wanting. The part preserved is 3°6 inches in length, the tail absorbing 
4D2 
