168 
ACTINOPTEETGII. 
are deeper than long, but those more posteriorly are about 
as deep as long; all are marked by very delicate longi¬ 
tudinal ridges. Traces of slender ribs occur, and all the 
neural arches bear curious laminar expansions. Portions 
of the pelvic fin-supports {'plv.') are distinguishable, and 
there are a few indications of very thin scales. 
EnnisJcillen Coll. 
The following specimen seems to belong to a species of Enclielurus, 
but is not satisfactorily determinable :— 
P, 9248. Imperfect distorted fish, nearly as large as the type spe¬ 
cimen of E. anglicus, wanting caudal extremity; Upper 
Cretaceous, Hakel, Mt. Lebanon. The characteristic 
cranium is exposed from above, and the left maxilla and 
mandibular ramus are well shown. There are also remains 
of a tubercular tritoral dentition on some of the inner 
bones of the mouth. The expansions of the neural arches 
cannot be seen. Eemains of the pelvic, dorsal, and anal 
fins occur. The scales are marked by radiating grooves 
in their covered portion. Leivis Coll. 
Family NOTACANTHID^. 
Trunk much elongated, the caudal region slender and tapering, 
with or without a diminutive caudal fin. Parietal bones partly in 
contact, but not completely excluding the supraoccipital from the 
cranial roof ; squamosals suturally united with parietals and com¬ 
pletely covering the otic region; snout a little produced; cheek- 
plates very delicate. kTandibular suspensorium inclined forwards, 
and gape of mouth small; premaxilla extended and excluding the 
maxilla from the upper border of the mouth ; teeth slender, never 
much enlarged. Opercular apparatus complete, with a few branchi- 
ostegal rays, but no gular plate. Vertebral centra much constricted, 
those of the abdominal region with very short and broad transverse 
processes ; ribs long and slender, inserted just below the neural 
arches. Intermuscular bones present, sometimes fused with the 
ribs. Pectoral arch connected with the skull by ligament. Fin- 
fulcra absent ; paired fins well-developed, the pelvic pair being 
remote; dorsal fin rudimentary, its supports being widely spaced, 
and the rays, when present, being represented chiefl)" b}'’ small 
spines; anal fin low and much extended, its anterior portion at 
least spinous. Scales thin and cycloid; lateral line distinct along 
the upper part of the flank. 
