DERCETID.1:. 
181 
fin. Anterior abdominal region excessively slender, and its vertebral 
centra about three times as long as deep, with much expanded 
transverse processes ; a series of 13 or 14 anterior vertebrae equalling 
the length of the head ; the other vertebral centra a little deeper 
in proportion to their length. Pelvic fins much larger than the 
pectorals, arising just in advance of the middle point of the trunk, 
the distance between the pectoral and pelvic pairs equalling twice 
the length of the head with opercular apparatus ; dorsal fin occup\lng 
less than the middle third of the trunk ; number of fin-rays probably 
as in Z. triqueter. Dermal scutes narrow, those on the dorsal and 
ventral border of the elongated abdominal region excessively 
attenuated ; anterior abdominal fiank-scutes narrow heart-shaped. 
It seems probable that the fragments named Deixetis tenuis by 
Pictet (Poiss. Foss. Mont Liban, 1850, p. 46, pi. ix. figs. 1-4) 
belong to this species; but they are too imperfect for certain 
determination. 
Form. Loc, Upper Cretaceous: Mt. Lebanon, Syria. 
48086. Type specimen figured by Davis, loc. cit. ; Sahel Alma. 
The end of the snout is broken away, and the flaking of 
the bone exposes some of the slender clustered teeth of 
the upper jaw. The delicate ovoid plate at the anterior 
border of the orbit is distinct; and a curved plate much 
broader than deep, just in front of the clavicle, may be 
the suboperculum. The very slender vertebrae of the 
somewhat distorted abdominal region exhibit the ex¬ 
panded transverse processes ; and the characteristic dermal 
scutes are distinct as far forwards the pectoral fin. 
The total number of vertebrae seems to be between 70 
and 80. The scntes on the ventral border become notably 
enlarged towards the base of the pelvic fins, which seem 
to have been larger than the pectorals. The long trans¬ 
verse processes of the vertebras are well shown in the 
region between the remains of the dorsal and pelvic fins. 
Further back one of the ventral caudal scutes is exposed 
in side view, dis])laying a small uncinate spine and one 
arm distinctly produced into one of the lath-shaped plates, 
which are very conspicuous. The anal fin is represented 
only by five fragmentary rays. The caudal fin is similar 
to that of L. triqueter. Leiuis Coll. 
49538. More imperfect fish about 0'23 in length; Sahel Alma. 
One of the pectoral fins, imperfect distally, exhibits eight 
rays; the other fins are indicated merely by fragments. 
