Part 44

Length 5 inc. 6 lin.

COLOUR.—Brown, but with some lighter specks and mottlings, more particularly on the lower jaw and on the fins.

Taken by Mr. Darwin at Tahiti. Probably a new species, but, as in the last case, the specimen is young and not easily determinable.

LOPHOBRANCHII.

FAMILY.—SYNGNATHIDÆ.

1. SYNGNATHUS ACICULARIS. Jen.

PLATE XXVII. fig. 3.

S. flavo-brunneus: corpore gracillimo, compresso, heptagono; caudâ quadrangulâ: vertice plano; cristâ occipitali parum conspicuâ; rostro longo, compresso, verticaliter capite angustiore, margine superiore acuto prope recto: pinnâ dorsali totâ multum ante medium longitudinis sitâ; pinnis pectoralibus parvis, anali minutissimâ, caudali distinctâ.

LONG. unc. 5. lin. 10.

FORM.—Very similar to the S. Acus, but the body rather more compressed. The angles are the same, and the middle lateral ridges of the trunk rise upwards in a similar manner to terminate behind the dorsal fin. There are about seventy transverse shields or plates in the whole length, eighteen of which lie between the gills and the vent. Head much compressed about the gills, contained with the snout about eight and a half times in the entire length. Crown nearly flat, with very little of an occipital ridge; profile falling obliquely, but not much out of a straight line; between the eyes a slight hollow. Snout elongated, a trifle more than half the entire length of the head, compressed, the upper edge sharp and nearly horizontal in front of the nostrils, vertically much narrower than the head.

The dorsal commences at one-third of the entire length, and occupies a space about one-tenth of the same, terminating before the middle: the number of rays is about forty or more. Vent about underneath the seventh dorsal ray. Anal extremely minute, of only one or two rays. Pectorals very small. Caudal distinct, much as in S. Acus.

COLOUR.—(In spirits.) Of a nearly uniform yellowish brown, paler underneath.

Habitat, Valparaiso.

This species, taken by Mr. Darwin at Valparaiso, would seem to represent in that quarter of the globe the S. Acus of the European seas, which, on the whole, it much resembles, though there are several slight differences on a close comparison. It is a female specimen, being without the abdominal pouch, and is probably not full-sized. The dorsal fin being a little injured, and the rays very delicate as well as close-set, it is hardly possible to tell the exact number. The anal exists, but it is so extremely minute that it might easily be overlooked.

2. SYNGNATHUS CONSPICILLATUS. Jen. PLATE XXVII. fig. 4.

S. griseus, fasciis transversis fuscis; genis albicantibus, vittis duâbus angustis longitudinalibus nigro-fuscis: corpore crassiore, subcylindrico, hexagono; caudâ quadrangulâ: vertice elevato; cristis occipitali et nuchali distinctis: oculis magnis prominulis: fronte declivi, in descensu sinnato: rostro brevi, gracillimo, subcylindrico: pinnâ dorsali paulo ante medium longitudinis desinenti: ano infra radium primum dorsalem sito: pinnis pectoralibus parvis, anali minutissimâ; caudali distinctâ.

D. 31; A. 3?; C. 10; P. 14. LONG. unc. 4. lin. 7.

FORM.—Body rather thick and somewhat cylindrical; the greatest depth and thickness nearly equal, the former being about one-twenty-seventh of the entire length. From the head to the vent hexagonal, the middle lateral ridges terminating abruptly, when opposite the commencement of the dorsal fin, without inclining either upwards or downwards. Fifteen transverse plates between the gills and the dorsal fin: only fifty-four in all, the tail not tapering so much as in many other species. Head much pinched in at the gills, but rather full and protuberant about the cheeks: its length ten and a half times in the entire length. Crown high and convex: a ridge commencing at the occiput passes backward to the nape. Eyes large and full, with somewhat of a spectacled appearance; their diameter equal to the whole depth of that part of the head; the orbits rising in ridges above them, with the intervening space concave. From between the eyes the profile descends in a sinuous curve to the base of the snout, which is short, slender, very narrow, and almost cylindrical. The length of the snout is less than half the entire length of the head; its breadth, vertically, only one-third the depth of the same taken behind the eyes.

The dorsal commences beyond one-third of the entire length, occupies one-ninth of the same, and terminates a little before the middle: nearly even, and rather high, more than equalling the depth of the body underneath. Vent about underneath the first ray, but almost in advance of the dorsal fin altogether. Anal extremely minute. Pectorals very small. Caudal rays distinct.

COLOUR.—Trunk greyish brown, with deep brown interrupted transverse fasciæ. In front of the dorsal, the fasciæ terminate at the middle lateral ridge, below which the sides are spotted. Dorsal fin also a little spotted. Cheeks whitish, with two very distinct narrow longitudinal vittæ extending backwards from the eyes to the posterior part of the opercle.

Habitat, Tahiti.

A well-marked species, and apparently undescribed. The only specimen in the collection is a female, and, like the last, perhaps not full-sized.

3. SYNGNATHUS CRINITUS. Jen. PLATE XXVII. fig. 5.

S. griseus; ventre, et maculâ operculari, nigricantibus: corpore crassiore, antice heptagono, postice quadrangulo, angulis acutis: vertice parum elevato; cristis occipitali et nuchali distinctis: rostro brevissimo, subcylindrico, capite angustiore, postice supra carinato, apice subrecurvo: cirris duobus, minutis, filamentosis, palpebralibus: pinnâ dorsali paulo ante medium longitudinis desinente; ano infra initium ejus sito: pinnis pectoralibus et caudali parvis; anali nullâ.

LONG. unc. 3. lin. 5.

FORM.—Body thickish, the greatest depth and thickness nearly equal, the former about one-twenty-fifth of the whole length. From the head to the vent heptangular; tail quadrangular: all the angles sharp and distinctly marked. The middle lateral ridges in the heptangular portion pass downwards at their extremities to terminate at the vent. Sixteen transverse plates before the dorsal: only fifty-two in the whole length. Head short, about one-eleventh of the entire length, not more compressed than the body. Crown not much elevated, but with distinct occipital and nuchal ridges. Orbits rising in ridges above the eyes, the interocular space being hollowed out: also a ridge commencing between the eyes, and passing forwards along the base of the snout, but not reaching to its extremity. Snout itself very short, its length only one-third the entire length of the head, narrower than the head vertically, nearly cylindrical, the tip slightly recurved. A few very short minute filamentous threads scattered about the head, more particularly one over each eye.

Dorsal placed much as in the last species, and terminating a little before the middle; the rays delicate and not easily counted, about twenty. Vent beneath the commencement of the dorsal. No anal distinguishable even under a lens. Pectorals very small. Caudal moderately distinct.

COLOUR.—Grey: a spot on the gill-cover, and the belly, dusky. The carinæ which form the edges of the under surface of the body are darker still, and shew a fine dark line on each side extending to the caudal.