rior margins are rotundate and entire, or very slightly undulated ; those on the anterior
part of the belly are much smaller than the others.
Head.—The vertex is covered with smooth skin, which, shrinking, shews in the
dried specimen a central obtuse ridge, and a lateral one over each orbit, better
marked, but tuberculated and interrupted. These are inconspicuous in the recent
fish. The operculum and sub-operculum form conjointly nearly a rectangle, having
its posterior angles slightly rounded off. The inter-operculum is acutely triangular,
and the pras-operculum, of a lunated form, unites with the sub-orbitar bones to cover
great part of the cheek, a small fleshy portion occurring only over the angle of the
lower jaw. The orbit is large and nearly round ; it is above one-half nearer to the
margin of the mouth than to the posterior edge of the operculum.
The nostrils are small, and placed between the anterior superior angle of the orbit,
and the intermaxillaries.
The mouth is moderately large. The intermaxillaries, forming about a third part
of the upper mandible, are narrow, and lie transversely, giving a truncated appearance
to the snout when viewed from above. They are articulated with the maxil-
laries, which have also a narrow oblong form ; and, when the mouth is extended,
they form its sides, descending perpendicularly to be connected by membrane with
the broad posterior part of the lower jaw ; an oblong pedicle is attached to the posterior
edge of each of the maxillaries. The lower jaw is large and strong, and has its
articulation under the centre of the orbit; about one-half of it, when the mouth is
open, projects beyond the upper jaw. Its symphysis, or extremity, is obtuse, forming
the segment of a circle. When the mouth is closed, the maxillaries are retracted
close to the orbit, the lateral margins of the lower jaw shut in under them, and a
transverse slit only is seen, formed at the extremity of the muzzle, by the intermaxillaries,
and obtuse end of the lower jaw.
Teeth.—A single row of small hooked teeth runs round the margins of the intermaxillaries,
maxillaries, and lower jaws. A double row, rather more minute, exists
on each side of the palate, and there is a small cluster on the anterior part of the
vomer. These are all conspicuous in the dried specimen. The tongue is smooth;
the superior pharyngeal bones are rough, with minute teeth.
The upper branchial arch is furnished with a row of rough subulate cartilaginous
processes; there are smaller and softer processes on the other arches. The bran-
chiogtegous membrane contains eight flat rays, the inner ones becoming gradually
more, curved.
The alimentary canal descends from the pharynx for two inches and a half, in form
of a straight tube, having its internal membrane disposed in coarse longitudinal
ru g * ; it then, dilates considerably, and bends upwards upon itself. This dilated
part resembles the stomach of the attihhawmegh in its structure, but its coats are
not so thick. The pylorus, which is much contracted, terminates the ascending part.
The rest of the intestine runs downwards in a straight line to the anus; its coats are
very thin, but two or three inches of its inferior part are strengthened by some circular
rugse of its internal membrane, and round its upper part seventeen or eighteen
caaca, from one-half to two inches long, are inserted within the space of three-quarters
of an inch. The liver is small, without lobes, and there is a large spleen attached
to the lower curvature of the stomach. The air-bladder is large, and communicates
with the oesophagus.
Fins.—The pectorals are scimitar-shaped, and pointed, and reach rather more than
half way to the insertion of the ventrals. The dorsal fin is probably by far the largest
in this genus; it contains twenty-four rays: the two or three first are small, but the
others, increasing rapidly in height, as their origin is more posterior, become more
and more branched, and cause the fin to play loosely like a flag over the posterior
part of the body; the insertion of the fin occupies about one-third of the length of
the body, and the extremity of its posterior ray, which is five inches long, reaches
as far as the adipose fin. The extraordinary size and beautiful colours of this fin
form the great ornament of the fish. The adipose fin is tongue-shaped, about one inch
long, and situate opposite the posterior edge of the anal. The ventrals are large,
obliquely fan-shaped, and placed opposite the centre of the dorsal. The anal fin is
rather small; it contains ten rays, besides two or three very short ones, which lie over
the base of the first one ; the others become shorter as they recede ; a naked space,
equal to the length of the insertion of this fin, is left between it and the tail. The
caudal has a shallow crescentic form, the lower lobe being slightly larger than the
upper one. Most of the fin is covered with very small scales, densely tiled.
B. 8. P.17. D. 24. A. lOf. V. 9: C. 20£.
-This beautiful fish inhabits strong rapids. Its stomach is generally filled with
gravel, or black earth. It bites eagerly at the artificial fly, and, deriving great power
from its large dorsal fin, affords much sport to the angler. Its rectum is filled with
black faeces. The ordinary length of the species is about sixteen inches, exclusive of
the caudal fin, or about twelve inches from the snout to the anus. As an article of
food it is inferior to the attihhawmegh. It is found only in the clear rivers to the
northward of Great Slave Lake.
In the figure, which is an accurate representation of the dried specimen, the posterior
part of the fin is scarcely produced enough, owing to a portion of it having
broken off in the carriage.