' I / '
firm state of preservation, it is hardly possible to say whether they are new or
not. In form, they differ hut little from the P . cyanophrys of Cuvier and
Valenciennes : still they are evidently not that species, and one point of
difference consists in the lateral line, which terminates beneath the end of the
second dorsal, and is not carried on to the caudal, as represented in the figure of
the above species in the “ Histoire des P o is s o n s th e eye too appears rather
larger; the forehead is hardly so much elevated, and the pectorals are shorter
than the head. Perhaps it may he the P . leucurus of the above authors ; though
this species is from the Indian seas, so that its range must be considerable if the
same. The description of the P . leucurus in the “ Histoire des Poissons” is too
short to determine this point. It is said to have been so named on account of its
whitish tail, all the other fins being black. In the present species, the fins are
likewise black, or at least dusky, except the caudal, which Mr. Darwin’s notes,
taken from the recent fish, state to have had “ a pink tinge.” In the same notes
it is added,—“ belly silvery white mottled with brownish black ; sides bluish with
dusky greenish m arkings; iris yellow, with dark blue pupil.” The fin-ray
formula is as follows :
D. 10-1/27 ; A. 3,'27 ; C. 17, & c.; P . 17 or 18 ; V. 1/5.
Tliough these specimens are small, they have the appearance of being nearly
full-sized. Cuvier and Valenciennes state that their specimens of the P . leucurus
do not exceed two inches in length.
S t r o m a t e u s m a c u l a tu s . C u v. et Val. ?
Stromateus maculatus, Cuv. et Val. Hist, des Poiss. tom. ix. p. 296.
F o r m . —General form so extremely similar to that of the S . Fiatola of the Mediterranean as to
preclude the necessity of a detailed description. G reatest depth one-third of the length : head
one-tifth of the same. Num ber of rays in the dorsal and anal fins somewhat greater than in
the S . Fiatola. The height of the dorsal also a little greater, being contained about three
times and a h alf in the depth: the fifth and sixth soft rays longest. Fleshy part of the tail
more slender. Pectorals about the length of the head.
B. 6; D. 7/41 ; A. 5/40 ; C. 17, besides several sh ort; P. 23 ; V. 0.
Length 8 inches G lines.
C o l o u r .— “ Silvery blue above, with regular circular leaden spots.”— D . The spots are small, and
of nearly equal size: they prevail from the back downwards to about the middle of the depth,
and advance a little on the base of the dorsal fin. The arrangement of them is much as
described in the “ Histoire des Poissons.”
H abitat, Chiloe, West Coast of S. America.
It is ju st possible that this may not be specifically the same as the S. maculatus
of Cuvier and Valenciennes, but it comes so extremely near that species that I do
not feel authorised in describing it as distinct without seeing more specimens.
It is stated by the authors above mentioned, that the fin-ray formula of the
S . maculatus is the same as that of the S . F iatola: in the specimen here described,
the number of rays in the dorsal and anal fins appear to me somewhat greater;
but as the spines of these fins are very minute at their commencement, and not
readily counted, nor very distinguishable from the soft rays, perhaps the discrepancy
may arise from a difference in the mode of computation. What is more to
be noted is, that the spots, although they agree in form and mode of arrangement,
are said by Mr. Darwin, in his notes taken from the recent fish, to have been
“ leaden;” whereas it is stated in the “ Histoire des Poissons” that they are
“ yellow.” Perhaps they may vary in colour according to the period of the year.
There is likewise a difference in locality as regards latitude. The S . maculatus
is said to be common in the m arket at Lima, and to have been brought also, both
by M. D ’Orbigny and M. Gay, from Valparaiso. Mr. Darwin’s specimen,
however, was taken as far south on the western coast of S. America as Chiloe.
Mr. Darwin’s collection contains another specimen, either of the same species
as that described above, or one so extremely similar to it as not to be distinguishable
in the case of this specimen, which is in too bad preservation to admit of an
accurate description of it being given. The following, however, are Mr. Darwin's
notes taken from the recent fish:—
C o l o u r .— “ Whole body silvery; upper part of the back iridescent blue, lower greenish ; spotted
with coppery-lead circular patches.”— D.
This specimen measures ten inches and a half in length. It will be observed
that the colour of the spots is still said to have been “ lead,” though inclining to
coppery. It was not taken at the same place as the other, but at Port St. Julian,
in central Patagonia; if therefore they are both referable to the S . maculatus, this
species will have been proved to have a wide range in point of latitude, and also
to occur on both sides of the S. American Continent, which is remarkable, considering
that it is found so high up the western side as Lima.
F a m i l y . — T E U T H Y D ID ® .
1. A c a n t h u r u s t r i o s t e g u s . B l. Schn.
Acanthurus triostegus, Cuv. ct Val. Hist, des Poiss. tom. x. p. 144.
-------------- Ilirudo, Bcnn. Fish of Ceyl. pi. xi.
This species, which appears to be well known, and to have been described by
several authors, was found by Mr. Darwin on coral reefs at the Keeling Islands.
Cuvier and Valenciennes observe that it has a wide range through the Indian and