Davis—On the Fossil Fishes of the Chalk of Mount Lebanon. 601 
been removed numerous radiating lines are exposed; they converge towards the 
antero-superior part of the operculum and expand towards its posterior outer 
margins. The orbit, maxillz, and other parts cannot be identified. 
The spinal column consists of thirty-three vertebree in the part preserved, the 
whole of which appear to be abdominal. Ribs, long and strong, are attached to 
each vertebra and extend with a sigmoidal curvature to the ventral surface of the 
body. Hzmal spines extend from the vertebra on the dorsal surface ; they are 
short and strong, and proceed to the under surface of the dorsal plates; the 
vertebre are longer than high, with well ossified centres, the body of the vertebrae 
contracted. The spinal column is situated very high in the body, but this may 
to some extent be displaced, though it has not the appearance of being removed 
from its normal situation. 
There is only one fin exhibited; it is 2°2 inches in length and is folded close. 
The rays at the basal part are strong and undivided; ten can be distinguished ; 
midway they bifurcate, and the distal extremity of the fin is much divided. The 
scales are medium size, 0°15 inch in length, with rounded posterior margin. 
The dorsal plates have been already referred to. 
Formation and Locality.—Soft chalk: Sahel Alma, Mount Lebanon. 
£x coll.—Lewis Collection, Robert Damon, Esq., Weymouth. 
Genus. Eurygnathus.* Davis. 
Fish of moderate size; head large, broad, depressed, with wide gape and 
formidable dentary apparatus; branchiostegal rays present; vertebral column 
strong and straight. Unpaired fins large, similar in form and construction. Outer 
rays of each lobe of the tail expanded and spinous. Paired fins medium size, 
abdominal. Scales thin, small. 
This genus approaches in several respects that of Ischyrocephalus, Von der 
Marck (‘‘ Fossile Fische, Krebse und Pflanzen aus dem Plattenkalk der jiingsten 
Kreide in Westphalen,” p. 28), the latter is distinguished by the possession of an 
adipose dorsal fin and a series of four bony plates extending in a line along the 
median dorsal surface, of which there is no evidence in the genus now described. 
M. Pictet instituted the genus Eurypholis for a group of fossil fishes from Mount 
Lebanon, which, he states, were evidently comprised in the family Halecoides, 
but which were apparently not represented by any living genera (‘‘ Description 
des poissons fossiles du Mont Liban., 1850,” p. 28). The genus is distinguished 
by the ventral fins being supported by a strong bone attached to the scapular 
cincture which makes the fishes thoracic. ‘Ce caracttre exceptionnel, trés-rare 
dans les Cycloides malacopterygiens, et qu’on ne retrouve que dans une petit 
* evpus, latus; yva8os, maxilla, 
