FAMILY: CLUPEIDAE

1. CLUPEA FUEGENSIS. Jen.

Mr. Darwin's collection contains a single individual of a species of Clupea from Tierra del Fuego so extremely similar to the young of the common Herring, that it might almost be mistaken for it. As it is small, and in not very good preservation, I shall merely point out some of its leading characters.

Depth of the body the same as in a young Herring of the same size. Belly carinated, but with the serratures not more developed than in that species. Teeth the same, and very minute. The maxillary does not slope inwards quite so much at its upper extremity, before uniting with the intermaxillary; but the mouth and its several parts are in all other respects similar. The same may be said of the pieces of the opercle, excepting that there is a more sensible notch near the upper part of the posterior margin of the gill-flap, much as in the common Sprat.

It differs also from the Herring in having the ventrals exactly in a line with the commencement of the dorsal, this last being placed a little further back than in that species.

D. 18; A. 19; C. 19, etc.; P. 18; V. 8

Length 3 inches

‘Caught at night, off Cape Ines, Tierra del Fuego, two miles from the shore, in thirteen fathoms.’ - D. The specimen is probably not full-sized.

 

2. CLUPEA ARCUATA. Jen.

The present species is from Bahia Blanca. The specimens, of which there are two, are also in bad condition like the last, and probably not full-sized.

Form. Body deep, with the ventral line swelling rather more outwards than the dorsal. Greatest depth a little exceeding one-fourth of the entire length. Very much compressed: abdomen carinated, and very sharply serrated, the serratures sharper than in the common sprat. A few minute teeth at the extremity of the lower jaw, and also on each side of the intermaxillary, near its junction with the maxillary; the lower half of this last finely serrated. Pieces of the gill-cover much as in the sprat; the subopercle rounded at the bottom, the opercle with a shallow notch near the upper angle.

The dorsal commences exactly in the middle of the entire length, excluding caudal. The ventrals are as nearly as possible directly beneath its first ray: these fins are very small, and shorter than in the sprat.

D. 18; A. 23; C. 19, etc.; P. 16; V. 7

Length 4 inches 2 lines

Colour. ‘Back blue; belly silvery.’ - D.

The second specimen is similar, only smaller. Both were taken in the month of September.

 

3. CLUPEA SAGAX. Jen.

A third species of Clupea , in Mr. Darwin's collection, likewise in bad condition, much resembles in general form the common pilchard.

Depth the same as in the pilchard, but the head larger and longer than in that species, being one-fourth7 of the entire length. Abdomen smoother; no appearance of any serratures in front of the ventrals. Lower jaw but little advance beyond the upper. No perceptible teeth, more than a few very minute serratures near the lower extremity of the maxillary. Diameter of the eye about one-fifth the length of the head. The form and veinings of the pieces of the opercle very much as in the pilchard, but the interopercle more developed. The posterior margin of the opercle and subopercle taken together is almost quite straight, without any emargination anywhere, and not far out of a vertical; the subopercle is cut nearly square at bottom. The preopercle is much veined: there are also some veins on the upper part of the opercle, and lower down on this last piece some very deep striæ, running parallel to its junction with the preopercle, as in the pilchard, but still more strongly marked.

The commencement of the dorsal is very little anterior to a middle point between the end of the snout and the base of the middle caudal rays. The ventrals are beneath the posterior half of the dorsal as in the pilchard. There are the same two elongated scales on each side of the caudal as in that species. The scales on the body, however, are much smaller than in the pilchard, with their free portions striated, the basal portions marked with some irregular curved lines running in a transverse direction towards the median line of the scale.

7 In the pilchard it is one-fifth.

 

D. 11; A. 18or 19; C. 19, etc.; P. 18; V. 8

Length 10 inches 6 lines

Habitat, Lima, San Lorenzo Island.

 

ALOSA PECTINATA. Jen.

PLATE XXV

A. corpore ovali, altitudine prope tertiam partem longitudinis aequante: ventre carinato, serraturis, praesertim inter pinnas ventrales et analem, acutis: maxillis subaequalibus, edentulis: preoperculo venoso; operculo striato: squamis pectinatis: pinnis ventralibus paulo ante dorsalem exorientibus

D. 16; A. 21; C. 19, etc.; P. 17; V. 7

Long. unc. 12

Form. Of an oval compressed form, the depth very considerable, equalling very nearly one-third of the entire length. Head contained about three times and three quarters in the same. Abdomen sharply carinated, with strong serratures, especially between the ventrals and anal. Jaws nearly equal, perhaps the lower one a little the longest; intermaxillary deeply notched; no apparent teeth anywhere. Eyes rather high, partly covered both anteriorly and posteriorly by a membranaceous veil; their diameter about one-fifth the length of the head; more than one diameter between them and the end of the snout. Subopercle obliquely rounded off at bottom, but the curvature of the posterior margin of the opercle and subopercle taken together not very considerable. Preopercle marked with vein-like ramifications; opercle similarly veined, and also striated below, as in the species last described, though more finely. Scarce any trace of a lateral line.

Scales moderately large, thin and membranaceous. One from the middle of the side of a sub-oblong form, the hinder angles rounded, its length only two-thirds of its breadth; the greater portion of the surface marked with exceeding delicate striæ, scarcely visible without a strong lens, the anterior margin pectinated, and with a slightly projecting lobe in the middle. The scales as they approach the tail, become longer in proportion to their breadth, the basal margin more rounded, and sometimes with a strongly projecting lobe in the middle. The pectinations are longest on the scales covering the nape.

The dorsal commences a little behind the middle point of the oval of the body, and the ventrals are attached a little in advance of that fin. The anal commences a little behind the termination of the dorsal, and reaches to the commencement of the fleshy part of the tail: the last ray in both dorsal and anal is slightly lengthened beyond the preceding ones. The pectorals reach to the ventrals, and are contained about once and two-thirds in the length of the head. Caudal deeply forked; the lower lobe a little longer than the upper one: the base appears to have been covered with minute scales. Above the pectorals is a thin membranaceous lanceolate scale, more than half the length of the fin: a somewhat similar scale in the axillæ of the ventrals, but shorter in proportion; another below those fins.

Colour. ‘Body silvery: dorsal scales iridescent with green and copper: head greenish: tail yellow.’ - D.

A second specimen agrees with the above in form, but is smaller, measuring only 71ž2 inches. The colours, when recent, according to Mr. Darwin's notes, were as follows: ‘Scales silvery iridescent; back especially greenish; caudal fin yellow: remarkable for a circular dark green patch behind the gill-cover.’ - D.

Habitat, Bahia Blanca.

This species was caught by Mr. Darwin in the net, on a sandbank, at Bahia Blanca. It is well characterized by its strongly-pectinated scales, and does not appear to have been noticed by authors; though it would seem in that respect to have some affinity with the Clupea fimbriata of Bowdich.8

8 Excursions in Madeira , p. 234, fig. 44.

 

 

ENGRAULIS RINGENS. Jen.

E. capite compresso, gradiusculo, quartam partem longitudinis totius aequante: rostro acuto, ultra maxillam superiorem mediocriter prominulo; mandibulâ angustâ, dentibus lateralibus (ut etiam in maxillâ) minimis: corpore compresso: pinnis ventralibus infra, vix ante, initium pinnae dorsalis exorientibus: squamâ longissimâ membranaceâ suuper pinnam pectoralem retrorsum productâ

D. 15; A. 19; C. 19, etc.; P. 16; V. 7

Long. unc. 5

Form. Closely resembling the common anchovy, but the head decidedly larger and longer, being one-fourth of the entire length.9 Eye larger, but bearing an equal proportion to the size of the head; also rather nearer to the tip of the snout in consequence of this last not being so acute and much produced. Lower jaw rather narrower, from the great compression of the head and body. Maxillary, and its fine serratures on the edges for teeth, similar.

The depth of the body is about one-sixth of the entire length. The dorsal commences at the middle point of the length, reckoning this last to the base of the caudal fork, and terminates a little before the commencement of the anal: the first ray is not half the length of the second and third, which equal three-fourths of the depth: the fifth and succeeding rays become gradually shorter than those which precede. The first ray in the anal is likewise very short, and scarcely one-third of the next following. The ventrals arise almost directly under the first ray of the dorsal, being scarcely at all in advance; when laid back, they do not reach half-way to the anal. Above the pectoral is a long membranaceous scale equalling, or very nearly, the fin itself.

Colour. Not noticed in the recent state. In spirits, it appears silvery, with the back and upper part of the sides deep dusky blue, the two colours separated by a well-defined line.

Habitat, Iquique, Peru.

This is probably an undescribed species of Engraulis; nor am I aware that authors have hitherto noticed any from the west coast of America. Mr. Darwin obtained two specimens which are precisely similar to each other. The species closely resembles the common European anchovy,10 differing principally in its larger head, and more backward ventrals in respect to the dorsal.

9 In the E. enchrasicholus, it is hardly one-fourth of the length, excluding caudal.

10 I am indebted to Mr. Yarrell for the loan of a specimen of our common anchovy for comparison.

 


 

 

FAMILY: PLEURONECTIDAE

Mr. Darwin's collection contains individuals of five species belonging to this family, besides the drawing of a sixth; but the specimens brought home are dry, and badly preserved. Two appear to have been previously noticed; but it is difficult to pronounce upon the other three with certainty, neither do they admit of being accurately described. These last, therefore, I shall not venture to name, but merely point out a few of their principal characters, adding the localities whence they were obtained.

The species, of which there is a drawing, I conceive to be certainly new; and as its characters are very distinguishable, I shall name it in honour of the gentleman, one of the officers of the Beagle, by whom the drawing was made.

 

1. PLATESSA ORBIGNYANA. Val.?

Platessa orbignyana, Val. in D'Orb. Voy. dans l‘Amer. Merid., Atl. Ichth ., Pl. 16, fig. 1.

Form. Oval; greatest breadth two and a half times in the length. Eyes on the left side, near together, and equally in advance. Teeth in a single row, sharp-pointed, moderately strong, rather widely separate: posterior extremity of the maxillary cut nearly square. Dorsal commencing in a line with the eyes, and leaving a space between it and the caudal. The lateral line takes a sweep over the pectoral. Upper or eye side of the body slightly rough, with the scales finely ciliated; under side smooth, the scales on this side not ciliated.

Colour. ‘Above dirty reddish brown; beneath faint blue: iris yellow.’ - D.

Length 8 inches 9 lines

Habitat, Bahia Blanca, where it is said to be plentiful.

This species agrees so well with the figure of the P. orbignyana in D'Orbigny's Voyage, that I have little hesitation in considering it the same - but as no description of this last has been yet published, it is still possible I may be mistaken.

 

2. PLATESSA _____?

Form. Very similar to the last species, from which it scarcely seems to differ, except in having the teeth smaller, and somewhat more numerous and closer together; also in the maxillary, which is more dilated at its posterior extremity, and more obliquely truncated. The scales are extremely similar.

Length 6 inches 6 lines

Colour. Not noticed.

Habitat, King George's Sound, New Holland.

 

HIPPOGLOSSUS KINGII. Jen.

PLATE XXVI

H. fuscus: corpore ovato, lato: oculis sinistris, haud valde approximatis: dentibus acutis, fortioribus: lineâ laterali anticè arcuatâ: pinnâ dorsali supra oculos initium capienti, dimidio anteriore humillimo, posteriore modicè elevato: ventralibus distinctis, haud anali continuis: caudali subquadratâ, radiis mediis caeteris paululum longioribus

D. 18 et 48;A. 51; C. 14; P. 11; V. 6

Form. Breadth, not including the dorsal and anal fins, half the length of the oval of the body. Eyes on the left side, apparently distant from each other about two diameters; the upper one a little behind the lower. Teeth sharp and strong, forming a very regular series. The lateral line takes a sweep over the pectoral fin. The dorsal commences above the upper eye; the first half, or until it gets above the extremity of the reclined pectoral, is very little elevated, and much lower than the rest of the fin, with the membrane apparently notched between the rays; the remainder of the fin attains a moderate elevation, and there is an abrupt transition from the former to the latter portion. The anal answers to the elevated portion of the dorsal: both these fins fall short of the caudal by a small space. Pectorals short, and of a somewhat triangular form. Ventrals very distinct, free, placed right and left, with the rays a little projecting beyond the membrane; which last character appears also in the dorsal and anal. Tail somewhat square, but the middle rays slightly projecting beyond the lateral ones in the form of an obtuse lobe.

Colour. Represented in the drawing of a uniform light brown.

Habitat, Valparaiso.

This is the species of which, as before stated, no specimen was brought home, but only a coloured drawing made by Mr. Phillip King, an officer of the Beagle, for Captain FitzRoy. The drawing appears to have been done with accuracy, and from it the above description has been taken. The fin-ray formula, however, was computed from the recent fish, the above numbers being marked upon the drawing.

The teeth appear to indicate this species as belonging to Hippoglossus rather than to Rhombus, though possibly it may be found hereafter to serves as the type of a distinct subgenus in this family. The form of the dorsal fin, if correctly delineated, is remarkable. The size of the fish is not stated.


 

 

RHOMBUS _____?

Form. Oval, approaching to rhomboidal. Breadth a little exceeding half the length. Eyes on the right side, near together, equally in advance, or the lower one perhaps rather more forward than the upper; between them a double osseous ridge. On the under side of the head, and nearly answering in position to the upper eye, is a deepish cavity, from whence proceeds a tentaculiform appendage four or five lines in length. Teeth very small, sharp, in scarcely more than two rows, and apparently confined to the under side. Lateral line sweeping over the pectoral. Dorsal commencing above the upper lip, and reaching nearly to the caudal, but leaving a minute space. Both sides of the body are smooth, but the upper one appears to have lost its scales. Pectoral on the eye side about three-fourths the length of the head.

Length 5 inches

Colour. ‘Above pale purplish brown, with rounded darker markings.’ - D.

Habitat, Bahia Blanca, Coast of Patagonia.

 

ACHIRUS LINEATUS. D'Orbig.

Achirus lineatus, D'Orb., Voy. dans L'Amer. Mérid., Atl. Ichth., Pl. 16, fig. 2

Form. Body oval, but with the dorsal and anal fins included, approaching orbicular; the greatest breadth rather more than half the length. Eyes on the right side, moderately near together, the upper one a very little in advance. Lower jaw longest, projecting beyond the snout. Teeth forming a velutine band, very minute, and scarcely sensible except to the touch, confined to the side opposed to the eyes. Preopercle distinct from the opercle. A few short thread-like cirri on the under side of the head; two at the extremity of the snout being rather longer and more conspicuous than the others. Lateral line nearly straight throughout its course, somewhat higher at its commencement than afterwards, but taking no sweep. Both sides of the body rough, with ciliated scales, but the upper one most so. The dorsal commences above the upper lip, and reaches, as also the anal, almost quite to the caudal: this last rounded. Pectorals entirely wanting.

Length 9 inches

Colour. Not noticed.

Habitat, Rio Plata.

This species was obtained by Mr. Darwin in the market at Buenos Ayres, where it is said to be eaten. It so exactly accords in form with the figure of the A. lineatus in D'Orbigny's Voyage , that I have little hesitation in considering it the same, though, from the specimen being dried, there are no vestiges left of the transverse lines. Whether it be the A. lineatus of any other author I am uncertain.

It approaches, however, very closely the Passer lineistransversis notatus of Sloane.11

11 Nat. Hist. of Jamaica , Pl. 246, fig. 2.

 

PLAGUSIA _____?

Form. Oval, but narrow, and much elongated for a Sole, the breadth in the middle being three and a half times in the length. Eyes on the left side, very small, and closely approximating, equally in advance, or if any difference, the lower one a little first. Mouth small, with velutine teeth on the supine side, but apparently none on the upper: snout a little produced in a point beyond it. The dorsal and anal unite with the caudal, which terminates in rather a fine point. No trace of any pectorals above or below. Scales strongly ciliated, especially above, and both sides of the body rough.

Length 7 inches

Colour. Not noticed.

Habitat, San Blas, Coast of Patagonia.

This species is very nearly allied to the Plagusia braziliensis of Spix's work,12 but it appears to differ in having the eyes one over the other, or the lower one perhaps a little in advance, instead of the upper one a little before the lower.

12 Pisces Brazil, p. 89, tab. L.