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Show 106 ZOOLOGY OF THE VOYAGE OF THE BEAGLE. h k d ercular pieces covered with large scales, which form two the lips naked; but the c ee s an op h d ' h k 0 1 terminating behind in a rounded angle. Scales on t e bo y rows on the c ee s. perc e · h 1 h h · · · h d th a d twenty-one or twenty-two m t e engt : t e entire very large '. . eight m t e a1 ep b' n with granulations, whJ.C h are partm. 1 1 y d1' spose d m. lm' es exposed portlOn of each sc e sea rous . . h d d N l n the vertical fins. The lateral line occupies t e secon towards the free e ges. o sea es o . l fi h t t·Jl 1't reaches a little beyond the end of the dorsal, where It becomes row of sea es rom t e op, 1 . . · · d b 1 · . · · th fourth row which at this pomt 1s the th1r : tu a pores m mterrupted, recommencmg m e ' . . some laces ramified, but the ramifications not very d1stmct. . . rfhe dorsal commences above the posterior lobe of the _opercle~ an~ 1s. of near~y umform h · h b h t The length of the rays in the soft portiOn, whiCh 1s shghtly h1gher than h eig t. t rou~ ou .t 'te one-third of the depth. The whole length of this fin is half the t e spmous, 1s no qm . · 1' t . 1 th The anal answers to the last half of the dorsal, and termmates m the same me ; en ue eng • . 1 . r h 1 the three spines are slender, and the first very short. Cauda: w1th th~ centra p_ortwn s 1g t Y convex, but the three outer rays above and below prolonged mto a pomt one-th1rd the length of the whole fin; the lower point a little longer than the upper. Pectorals about one-fifth of the entire length, pointed, with the upper rays arcuate. Ventrals immediately beneath them, one-third shorter. . CoLOUll.-" Fine verditer blue, with some yellow stripes about the head and fin.s."-~.-The dr1ed skin is nearly of a uniform brown, but the snout and cheeks are. much .vaned w1th green_: tb_e jaws also are green. A bright green patch in front of the eye, 1mmed1ately beneath wh1ch IS a pale frrenum, probably yellow in the recent state. Dorsal and anal green: the former shews some trace of a lighter narrow band running longitudinally below the upper edge of the fi~; the latter exhibits a very distinct fascia running along the middle. Caudal pale g~een, With the upper and lower edges of a much deeper tint. V entrals in like manner edged w1th green. Pectorals wholly dusky. Habitat, Keeling Island, Indian Ocean. In so extensive a genus as the present, and one in which so much general similarity prevails amongst the species, the task of determining whether any particular one has been described before is extremely difficult. I can only say that the species which I have here ventured to characterize as new has been carefully compared with the descriptions of aU those noticed in the " Histoire des Poiss_ons:" and though there are several to which it is nearly allied, there is none to whJCh It can be referred with certainty. It seems to approach nearest the S. vm·iegatus, but that species is said to have the caudal square, by which I presume is ~eant that the upper and under rays are not prolonged into a point, as is the case m so many species of this genus, and in the one here described. This species was taken by Mr. Darwin at the Keeling Islands. 2. ScAnus GLOBICEPS. Cuv. et Val. S. globiceps, Cu'IJ. et Val. 1-Iist. des Poiss. tom. xiv. p. 179. FoRM.-Oblong-oval, very much compressed throughout: the dorsal and ventral lines nearly . of equal curvature. Greatest. depth contained about three times and one-third in the entue FISH. 107 length: thickness twice and three-fifths in the dcp~. Head one-fourth of the entire lenoth 0 ' rather _elevate_d _at the nape, the forehead convex, whence the profile descends nearly in the arc ~f a c1r~le, g~vmg the snout a blunt and rounded appearance. The height of the head, taken m a vertteal line through the eyes, equals nearly but not quite its own length. Mouth small, the gape not reaching half-way to the eye. Jaws very slightly crenated on their cutting edges, the true teeth appearing on the outer surface like minute scales. At the posterior angle of each jaw, and on each side, are two sharp canines projecting horizontally from the corners of the mouth, eight in all. Eyes rather small, their diameter contained six-and-a-half times in the length of the head, situate a little above the middle of the cheek, and a trifle nearer the extremity of the snout than the posterior margin of the opcrcle. The nostrils consist of two minute orifices a little in advance of the eye, and a little distant from each other, the posterior one largest and kidney-shaped, the anterior round and nearly closed by its membranous border. A cluster of minute pores above and behind the eyes, and a few others scattered about the snout. Scales on the body very large, increasing in size at the base of the caudal, where there are three very large ones covering the rays of that fin for half their length or more: twenty-three in a longitudinal line, and nine in the depth. Each scale of a roundish form anteriorly, the basal portion with a projecting lobe in the middle of the hinder margin, and with thirty-one strire in the fan ; the exposed portion finely striated and granulated, with a broad membranaceous border: those on the caudal nearly three times as long as broad, but the ordinary ones with the length and breadth nearly equal. Lateral line interrupted; the upper portion running nearly straight at about one-fourth of the depth, till opposite the end of the dorsal, where it inclines downwards: tubal pores very distinctly ramified. Dorsal very low, its height, in the middle of its length, being ~carccly more than oneeighth of the depth: the soft rays slightly higher than the spinous, and increasing in length backwards. Anal answering to the last half of the dorsal, and terminating in the same line : three spines at its commencement not stouter than the soft rays, the first very small. The last soft ray ,in both dorsal and anal double. Caudal with the points about one-fourth of the rest of its length; when spread, the interval is rectilineal, but when the rays are closed the whole appears crescent-shaped. Pectorals a little shorter than the head, of a somewhat triangular form, the rays gradually decreasing in length from the uppermost to the lowermost. Ventrals pointed, about two-thirds the length of the pectorals, and immediately beneath them. A large oblong lanceolate scale between the ventrals, nearly half their length: also an oblong scale in the axilla of each, equalling the last of the soft rays. D. 9/10; A. 3/9; C.13, &c.; P. 13; V.l/5. Length 11 inches. CoLOun.-Not noticed in the recent state. In spirits, it appears bluish grey on the back and sides with small round whitish spots, the margin of each scale being defined by a purplish line; paler on the belly: a white transverse line in front of the eyes passing from one to the other; anterior part of the snout, mouth, cheeks, and lower part of the head, yellowish white. Dorsal and anal pale, the former with three narrow longitudinal purplish lines, the latter with one. A portion of the under surface of the pectorals, extending from the third to the fifth ray, and |