612 Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 
R. robustus; it is situated one-third of the height of the head below the cranial 
surface, and 0°25 inch in front of the occiput. The opercular bones are narrow 
antero-posteriorly, but extend to a considerable height. The impression on the 
matrix show a number of branchiostegal rays to have been present, which have 
disappeared probably on the opposite matrix ; the rays are shorter and stiffer than 
those of Rhinellus robustus. 
The spinal column consists of the small number of twenty-four to twenty-six 
vertebra ; the articulatory surfaces are expanded, the central portion contracted ; 
the length of each vertebra is equal to its diameter. Neural and hmal spines 
spring from each vertebre in the caudal region. The ribs are long and slender, 
extending diagonally backwards. 
The dorsal fin is large, having about a dozen rays 0°3 of an inch in length; its 
base extends 0:4 of an inch, and it is separated by 0°2 of an inch from the head. 
The anal fin is midway between the ventrals and the caudal; its size or extent is 
not well defined. The caudal fin is large; the diameter between the outstretched 
lobes is 1:1 inch, each being 0°5 of an inch in length; the fin is deeply cleft, 
the rays strong, closely articulated, and, so far as can be observed, they are only 
once divided. 
The pectoral and ventral fins are small; they are both low down on the 
abdominal region. The pectorals are immediately behind the operculi; they are 
separated by a distance of 0°35 of an inch from the ventral fins. The anterior 
ray of each ventral fin is opposite the median portion of the dorsal; it is more 
posteriorly placed than in either of the preceding species. The scales are not 
preserved. 
The distinguishing characters of this species have to some extent been already 
indicated in its excessively long beak-like snout and short body. The minute, 
sub-conical teeth, the small number of its vertebra, and the backward position of 
the ventral fins also serve to separate it from preceding species. 
Formation and Locality—Hard gray chalk: Hakel, Mount Lebanon. 
Ex coll—Lewis Collection; R. Damon, Esq., Weymouth. 
Rhinellus laniatus, Davis. 
(BI. xxxvin, figs. 6) 72) 
The specimen exhibits the;form? of the body, the relative position of the fins, 
and the internal arrangement of the bones. The extremity of the jaws are 
broken off and a part of the fins hidden in the matrix. The part preserved is 
10:0 inches in length from the snout to the peduncle of the tail; of this length 
the head occupies 40 inches. The greatest depth of the body is 1°65 inch. 
The head is large and the jaws powerful. The occipital region is 1*5 inch 
