542 Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 
The fish is very rare; it was described by Costa in 1855, and, so far as I 
am aware, this is the only specimen since found; it forms a part of the 
collection made by Professor Lewis, and is in good preservation. 
The head is 1:0 inch in length from the snout to the posterior margin of 
the gill cover. The orbit is advanced and superior. The mouth is small, the 
jaws straight, and armed with short conical teeth, of which a few may be 
seen in proximity to the jaws. The opercular bones are longer than broad, 
convex posteriorly, and concave in front. 
The spinal column is slender, the vertebrae rather longer than they are deep. 
The vertebre are twenty-eight in number, of which sixteen are caudal. The 
ribs are fine and short; the neural and hemal apophyses are stronger, slightly 
curved, and extend three-fourths the distance between the spinal column and 
the outer margin of the body. Interspinous bones support the dorsal fin the 
whole length of the back, and also the anal fin so far as it extends. The 
interspinous bones are quite double the number of the spinous. A strong 
internal bone extends from the anterior rays of the anal fin to the vertebre ; 
it is straight except the lower extremity, which is expanded forwards in a 
triangular form, ending in a point on the median abdominal line. 
The dorsal fin extends the whole length of the back, from the occipital 
region of the head to the base of the tail; it is composed of numerous uniform 
branching rays, supported by an equal number of interspinous bones. The 
first three rays are spinous; the third, the longest, is 0°35 inch in length, 
accuminate, and directed backwards; the second and first rays are smaller and 
relatively shorter. The anal fin extends from the base of the tail forwards 
1-0 inch; it is composed in a similar manner to the dorsal, and also has three 
spines in front of the fin; they are stronger than the dorsal spines, and are 
supported, as stated above, by a strong internal bone. The caudal fin, judging 
from the basal portions of the rays which are preserved, was tolerably strong; 
a small number of rays are preserved, but in a crushed condition. The peduncle 
of the tail is 2°6 inches in height. 
The pectoral fin is 0:4 inches in length, comprising a considerable number of 
fine rays. It is situated at one-third the height of the body above the ventral 
margin, on the side immediately behind the opercular apparatus. A strong 
straight process descends diagonally from the base of the pectoral fin to the 
anterior margin, and probably indicates the position, or was the point of attach- 
ment, of the ventral fin; it is midway between the anterior rays of the anal 
fin and the head. 
As already observed, this genus was instituted by Professor Costa. When 
MM. Pictet and Humbert published their ‘ Nouvelles recherches,” in 1866, they 
remark, in writing of this genus: ‘‘Nous plagons avec doute a la fin de la 
famille des Chromides ce genre que nous n’avons vu en nature, et dont nous 
