158 UPPER CRETACEOUS TELEOSTS 
of the two limbs is expanded and flattened vertically. The supracleithrum articulates 
with the postero-medial part of the post-temporal. 
The supracleithrum is long and blade-shaped with a thickened anterior edge. 
The cleithrum is large and curved and expanded above the insertion of the fin. The 
endoskeletal girdle is attached to the internal face of the cleithrum, and the coracoid 
extends forwards to contact the cleithrum at the anterior end. Four pectoral fin 
radials support the fin rays and are slightly elongated and mesially constricted. 
Two postcleithra are attached to the rear edge of the cleithrum. The dorsal post- 
cleithrum is the larger, the ventral merely a narrow splint of bone. 
The pectoral fin is composed of 14 rays, the first being the longest. All the rays 
are segmented and most of them, if not all, appear to be branched. 
Pelvic girdle and fin. The triangular pelvic bones are sutured together in the mid- 
ventral line. Each is thickened posteriorly to form a prominent condyle supported 
by a thickened, lateral ridge. The pelvic fin has g rays, all of which are segmented, 
but several appear to have been unbranched. At the base of the fin is a small 
asymmetrically placed pelvic splint bone. 
Vertebral column. The vertebral column is shown in the restoration, Text-figure 
71. It is composed of 30 vertebrae, of which 16 are caudal. The centra are 
slightly longer than deep and mesially constricted. The neural arches are not 
fused to the centra anteriorly, although the more posterior neural arches have a 
more intimate connection. The neural spines originate from the anterior end of 
each neural arch. The precaudal vertebrae bear very small transverse processes 
which elongate on the last three or four precaudal vertebrae. Long, curved, 
flattened pleural ribs articulate with the small transverse processes. The haemal 
arches are extended into prominent, curved haemal spines. Zygapophyses are 
present on both the dorsal and ventral surfaces of the vertebrae, but are most 
pronounced in the ventral caudal region. Epineurals and epipleurals are present 
on the first 20 vertebrae. 
Median fins and tail, The median fins are shown in the restoration, Text-figure 
71. The dorsal fin consists of Ir rays and is situated in the second quarter of the 
back. The second or third ray is the longest and much in excess of the basal length 
of the fin. The first ray is short and unbranched, the second is longer and also 
unbranched, although both are segmented. The subsequent rays are branched and 
segmented. The radials are long, flattened and unexpanded except in their articula- 
tory head regions. Between the occiput and the origin of the dorsal fin, four accessory 
radials are present. The most anterior accessory radial is associated with the 
neural spine of the first vertebra. This association between accessory radial and 
neural spine may only have been ligamentous. 
The anal fin is positioned behind the level of the rear of the dorsal fin and mid- 
way between the pelvics and the caudal. Nine rays are present in the anal fin ; the 
first is short and unbranched although segmented, the second is long and unbranched, 
and the remainder of the rays are branched and segmented. 
