9 
or less coated with ganoine; pectoral rays all articulated; the dorsal opposed 
to the space between the pelvic and anal fins; caudal fin forked. Scales 
partially sculptured with irregular transverse furrows and dots, and the hinder 
free margin usually serrated. 
Obs . — This genus, as re-defined by Traquair (Quart. Journ. Geol. S c., 
vol. xxxiii, 1877, p. 557), has hitherto been known with certainty only from 
the Upper Permian of Europe. The new Australian species now described, 
however, seems to he a typical form. 
Pal.*oniscus crassus, sp. nov. 
Pla'.c II, Figs?. 3, 4. 
Obs. — There arc two examples of this species worthy of description, 
and a fragmentary isolated head may probably be ascribed to it : — 
(a) The type specimen, incomplete at each end (PI. IT, Pig. 3). 
( b ) Portion of dorsal region of trunk (PI. II, Pig. 4). 
(c) Internal cast of the greater part of the head, doubtfully of this fish. 
Sp. Char. — A stout species, attaining a length of about 0'5 m. Depth 
of caudal pedicle contained two and a half times in the maximum depth of 
the abdominal region, which equals about one-third of the length from the 
pectoral arch to the base of the caudal fin. Pelvic fins arising slightly nearer 
to the anal than to the pectoral pair ; dorsal fin arising opposite the hinder 
end of the pelvic pair, deeper than long, and its maximum elevation exceeding 
half the depth of the trunk at its insertion. Principal flank-scales deeper 
than long and ornamented with fine, oblique, transverse grooves and ridges ; 
ventral scales deeper in proportion to their length than usual in Palceoniscns. 
General Form. — The type specimen is sufficiently well preserved to 
exhibit the general proportions noted in the specific diagnosis, and shows 
that the back was only very slightly arched in advance of the dorsal fin. The 
relative size of the head and caudal fin is unknown. 
Head and Dentition . — The binder half of the bead is seen in tbe 
type specimen partly from below, partly from tbe left side; but tbe bones 
are so much broken and traversed by a network of fissures that neither 
ornament nor outlines arc distinct. Tbe rather slender binder half of the 
mandible (PI. II, Pig. 3, md.) and the hinder expansion of the maxilla (mx.) 
§8125 1 > 
