_C. capite compresso lævi: ore parvo, cirris maxillaribus ad utrumque
angulum duobus, haud ultrà oculos pertingentibus; labro inferiore
reflexo, et in duos cirros breves membranaceos producto: spinâ
pectorali compressâ, forti, margine interno leviter dentato, externo
lævi, quintam partem totius longitudinis æquanti: caudali bifurcá,
lobis æqualibus acuminatis._
D. 1/7—1; A. 6; C. 14, &c.; P. 1/7; V. 6.
LONG. unc. 1. lin. 10.
FORM.—General form resembling that of the _C. punctatus_. Depth, at
the commencement of the dorsal, one-third of the length, excluding
caudal: thickness at the pectorals three-fourths of the depth. Head
slightly compressed, its height very little less than its length,
this last, measured to the gills, being rather less than one-fourth
of the entire length. Profile falling from the dorsal in one regular
slope, and nearly rectilineal till it arrives before the eyes, where
it curves downwards, making the extremity of the snout obtuse. Mouth
small, the upper jaw a little projecting; two maxillary cirri at
each angle; these nearly equal; the lower one a little the longest,
reaching to beneath the middle of the eye: also two short cirri,
only half the length of the maxillary ones, pendent from the
reflexed lower lip, a little separate from each other, one on each
side the middle. Teeth so minute as hardly to be distinguished; a
row can just be felt on each jaw, and on the vomer. Head smooth. The
number of dorsal laminæ twenty-one; that of the ventral twenty.
Pectorals a little exceeding the length of the head; the spine nearly
as long as the fin itself, but not exceeding one-fifth of the entire
length; very strong, compressed, and sharp-pointed, with a few fine
teeth or serratures on the inner margin, but smooth on the outer.
Height of the dorsal more than half the depth, and a little more
than its own length, this last equalling the space between it and
the adipose: the spine strong, and similar to that of the pectoral.
Anal directly underneath the adipose, and hardly occupying more
space. Ventrals shorter than the pectorals, attached beneath the
last third of those fins, or under the second soft ray in the
dorsal, and scarcely reaching more than half-way to the anal: the
first ray, as well as that of the anal, somewhat hispid. Caudal
forked for half its length, which about equals that of the head: the
lobes equal and pointed.
COLOUR.—(_In spirits._) General colour yellowish brown, with dusky
spots and mottlings: breast and edge of the abdomen whitish.
Pectorals, ventrals, and anal, almost wholly dusky: dorsal and
caudal spotted.
This species, in its general character, approaches so extremely near the
_C. punctatus_ of Valenciennes, that perhaps I am in error in
considering it distinct. But it is remarkable for possessing, in
addition to the four usual maxillary cirri, two labial, which are
neither represented in D’Orbigny’s figure,[33] nor noticed in the
description given in the “Histoire des Poissons,” and which therefore I
infer are not present in that species, as they could hardly have been
overlooked, or been deemed unimportant to be noticed. The maxillary
cirri also, which in the _C. punctatus_, reach, according to
Valenciennes, to the gill-opening, if not beyond it, here only attain to
beneath the middle of the eye; and this character is invariable in five
specimens which Mr. Darwin has brought home. Judging from the
description, there would seem to be one or two further differences: the
profile appears to be more rectilineal, the pectoral spine shorter, and
smoother on its external margin. The colours are on the whole similar,
but the pectorals and ventrals darker: the latter, which are said to be
yellow in the _C. punctatus_, are here quite dusky in every one of the
specimens.
The exact locality in South America in which Mr. Darwin obtained this
species is uncertain, as the specimens have lost their attached labels.