Art. XXVII.—On a new Fish.
[Read before the Westland Institute, 8th January, 1879.]
The following description is of a new genus of fish, four specimens of which were obtained by myself on the 18th of May last, on the Hokitika beach. It has very marked peculiarities. The single dorsal, and the stout spinous rays in both it and the anal, connected by a perforated membrane, presents entirely distinct characters from any previously described genus. The most nearly allied appears to be the genus Brama. There is a possibility that the specimens obtained are young, but the characteristic points described below appear uniformly in them all.
Group 5. Coryphœnina.
Genus nov. Discus.
Body compressed and elevated; general form circular-pointed at snout and tail. Head and lower portion of body scaleless, minute scales on
upper portion of body and tail; cleft of mouth very oblique. A single dorsal, which, like the anal, is composed of stout spinous rays connected at their mid-length by a membrane having a breadth of one-third of their length, leaving apertures between the base of the rays. Caudal forked, ventrals slender; a single series of minute teeth in the jaws, finely pectinate; branchiostegals four; air-bladder large.
Discus aureus, sp. nov.
B.4, D.26, A.21, V.7, C.3/16/3, P.17.
The greatest height of body is two-thirds of length, and is vertical to the origin of the dorsal and ventrals; head equal to half height; snout equal to half, and interorbital space equal to one quarter greatest diameter of orbit, which is equal to half length of head; a depression extends down the snout; greatest thickness of body above the pectorals, and equal to greatest diameter of orbit; the upper maxillary extends to the vertical, below the centre of the eye; colour silvery, with minute bronze spots, with a dorsal margin of a similar colour, extending from behind the orbit, where the depth equals half orbit, to the caudal; pectorals yellowish brown, others dirty white.
Total length, 2 ¾.
Four specimens cast up on Hokitika beach.