356 
ACTINOPTERYGII. 
having been subsequently met with in the Collection. Of 
the cranium, only the highly-ornamented posterior portion 
of the roof is exposed (fig. 4 «), and the parietals ( pa .) 
are shown to be very small, the squamosals ( sq .) extending 
about twice as far forwards, and the frontals ( fr .) uniting 
in a wavy median suture. The smooth hinder margin of 
the cranial roof must have been deeply overlapped by the 
large supratemporal plates, of which the outermost is 
preserved on the left side. The rostral half of the skull 
is shown in irregular transverse section, and the pterygo¬ 
palatine arcade exhibits a large laminar bone, apparently 
the entopterygoid, covered with closely-arranged tubercular 
teeth, which become elongated towards the inferior margin 
and are nearly as large on the ectopterygoid (? or palatine) 
as on the maxilla. On the right side the greater part of the 
maxilla {mx.\ with an elongated supramaxilla ( s.mx .) on 
its hinder half, is preserved, showing some traces of 
ornament and the nearly straight dentigerous border; 
the mandible is also preserved, but more imperfectly, and 
tall conical teeth seem to occur on the splenial as viewed 
in transverse section. Beneath the mandible is part of a 
large, thin, ornamented plate, evidently the gular. One 
large cheek-plate (s.o.), with sparse radiating ornament, 
is also shown on the right side. The post-temporal plates 
are long and narrow, and ornamented in their exposed 
portion. Two fragments of the operculum {op.) on the 
left side are ornamented, and the suboperculum {s.op.) on 
the right side is more than half as deep as the operculum. 
The last-named and remaining characters are indicated in 
the published figure and description. Purchased , 1871. 
Neorhombolepis valdensis, sp. nov. 
[Plate VIII. fig. 5.] 
Type. Imperfect fish; British Museum. 
A species about as large as the type, similarly known only from 
an imperfect specimen. Principal Hank-scales and many of the 
narrow ventral scales extremely finely pectinated on their hinder 
margin; vertebral centra in the posterior abdominal region rela¬ 
tively longer than in N. excelsus. Other characters, so far as 
known, as in the latter species. 
Form. A Loc. Walden : Sussex. 
