Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 611 
slender, and extend backwards; their whole length cannot be clearly discerned 
because they are doubled by the position of the fish. 
The dorsal fin is 0:7 of an inch behind the occiput; it is supported by ten 
rays, the longest 0°7 of an inch in length. The rostral portion of the head or 
beak is 0°5 of an inch in length and 0°15 of an inch across the proximal portion, 
diminishing to 0:1 inch a short distance from the end. The termination of the 
beak is peculiar; at 0°1 inch from the end the bony framework suddenly expands 
and forms a process on each side which resembles a hammer; the termination 
of the beak is obtusely pointed. The right and left ramus of the jaw are separate 
until the end is nearly reached, when they gradually meet and coalesce. 
Rhinellus curtirostris is remarkable for its long body, small head, and short 
jaws; the most peculiar feature consists in the hammer-like enlargement of the 
distal end of the jaws. The position of the dorsal fin is more advanced than in 
either of the two specimens from the soft chalk at Sahel Alma. It is possible 
that the peculiar form of the termination of the jaws may be found to be of 
generic importance. This specimen is, however, imperfect, and for the present it 
will be retained in the genus Rhinellus. 
Formation and Locality.—Cretaceous: Hakel, Mount Lebanon. 
£x coll.—Lewis Collection; R. Damon, Esq., Weymouth. 
Rhinellus longirostris, Davis. 
(PE mxxyin., fied.) 
This beautiful little fish, like the preceding one, is from the hard gray chalk ; 
it differs from all others hitherto described in the large size of the head and 
immensely long jaws in proportion to the other parts of the body. The length 
of the fish, from the tip of the snout to the peduncle of the tail is 3-4 inches ; of 
this length the head and jaws comprise nearly two-thirds, or 2°2 inches, the length 
of the body being 1:2 inch. The greatest height of the body is 0:55 inch 
immediately in front of the dorsal fin, and posteriorly the body tapers to the 
base of the caudal, where its height is 0°2 of an inch. 
The post-orbital region of the head is 0°65 of an inch; from this point the 
head and snout extend forward with a concave flexure on the upper surface, 
and with a straight horizontal base. The terminations of the jaws are pointed, 
the lower one turning upwards very slightly at the tip. The mandible is 1-9 
inch in length, 0°15 in height near the articulary base, and thence gradually 
diminishes to an acute point. The pre-maxillary forms the terminal part of the 
upper jaw, and is 1-3 inch in length, the maxilla occupying the remaining portion. 
The jaws are armed with a long series of sub-conical teeth, very minute, only to 
be distinguished when magnified. The orbit is less than in R. furcatus or 
