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Show 108 ZOOLOGY OF THE VOY .AGE OF THE BEAGLE. forming a longitudinal fascia, purple ; the rest of those fins, as well as the caudal and ventrals, pale or nearly colourless. Habitat, Tahiti. This species was taken by Mr. Darwin at Tahiti. It so nearly answers to the description of the S. globiceps of Valenciennes, brought by MM. Garnot and Lesson from the same locality, that I cannot suppose it to be distinct. This specimen, however, appears to have more spinous teeth at the corners of the mouth. 3, SCAUUS LEPIDUS. Jen. S.fuscus, capite et pinnis purpureo-ct£rulco tinct is: fronte pm·um eleva to, ceque ac rost1·o continue et gradatim proclivi; hoc apice obtuso: maxillis exterius lt:evibus, ma1'ginibus vix crenatis; canino ad angulum oris in maxilla injerio1·e unico, in superiore Jwtlo: liiUd laterali distincte ramosd :·pectoralibus subtrianguiis: caudali subt:equali, radiis extends mediis vix longioribus. D. 9/10; A. 3/9; C. 13, &c.; P. 13; V. 1/5. LoNG. unc. 8. lin. 7. FoaM.-General form not very dissimilar to that of the last species, but the crown and nape less elevated, whence the profile falls in a more gradual slope: snout, nevertheless, blunt at the extremity. Depth of the body very nearly one-third of the entire length. Head about onefourth of the same. The height of the head is about four-fifths of its own length. Jaws smooth externally, the true teeth appearing like minute scales on their surface, the cutting edges scarcely at all crenated: only one laterally projecting canine at each corner of the lower jaw. none in the upper. Diameter of the eye one-sixth of the head. Dorsal not quite so low as in the last species; its height in the middle of its length about one-seventh of the depth. Caudal nearly even, the upper and lower rays being scarcely longer than the others. Pectorals and ventrals similar, but the scale between the latter shorter and more rounded. Scales on the body large, the free portions finely striated and granulated, with a broad membranaceous border : three large ones at the base of the caudal, as in the last species. Lateral line distinctly branched, the ramifications irregular and varying on each scale; in some instances only one long stem extending nearly to the margin of the scale, with one or more lateral twigs ; in others, two, three, or even four distinct stems, either simple or ramified. CoLOUR.-( In spirits.) Of a nearly uniform dark brown, with some faint traces of purplish blue about the head and fins, which possibly may have pervaded some parts of the body also in the recent state. Habitat, Tahiti. This species was taken with the last, and notwithstanding it presents two or ~hree obvious differences in respect of form, as well as of colour, it is just possible It may be the same in a younger Rtate. I think it not improbable that the points of the caudal may elongate with age, the forehead become more gibbous, and the FISH. 109 spinous teeth more numerous. If it be distinct it would seem to be undescribed · though the colours not having been noticed in the recent state renders it difficul; to speak with certainty on this point. For the same reason, the specific character may perhaps hereaftet· be found to require alteration. 4. ScAnus ---? Mr. Darwin's collection contains another species of Scm·us from the Keeliug Islands, which may probably be distinct from all those hitherto noticed, but which being in rather a bad state of preservation, I shall content myself with describing as well as I can, without affixing any name to it, lest in the end it prove not new. Many of the species enumerated in the "Histoire des Poissons" having only their colours noticed, it requires that these should have been observed more in detail than what Mr. Darwin's notes furnish in this instance, in order to decide whether it be identical or not with any of those spoken of in that work. FonM.-A tolerably regular oval, somewhat attenuated at each extremity: dorsal and ventral linee of equal curvature. Nape not at all elevated, and the profile on the whole falling very regularly and gradually from thence to the end of the snout, though there is a slight eminence on the forehead. Depth one-fourth of the entire length. Jaws smooth externally, but with the true teeth very distinct upon their surface, and much more so upon their cutting edges than in either of the last two species. One horizontally projecting canine at each corner of the upper jaw, but none in the lower. The terminating lobe of the opercle is slightly emarginated behind, the membrane projecting immediately above the notch in the form of a short salient point. Lateral line interrupted, the upper portion nearly straight, and not inclimng downwards at its posterior extremity: the tubes very slightly ramified, and many of them quite simple. The scales on the body are very finely granulated and striated: there are no large ones at the base of the caudal. Dorsal and anal low: height of the former contained four and a halftimes in the depth of the body, and exactly equalling the distance from the upper edge of the back to the lateral line. Pectorals somewhat triangular, the uppermost ray of all a little arcuate. Scale between the ventrals one-third the length of those fins. Caudal slightly crescent-shaped, when the rays are closed: when spread, all the middle rays appear even, the uppermost and lowermost projecting very slightly beyond them. D. 9/10; A. 3/9; C. 13, &c.; P. 14; V. 1/5. Length 6 inches. CoLoUR.-" Body dull reddish and greenish, the colours being blended and mottled: fins banded lengthwise with vermillion-red: head with waving bright green lines."-0.-No trace of bright colours remains in its present state, and the only indication of markings is a narrow crescentshaped band across the middle of the caudal. |