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Show 4 ZOOLOGY OF TilE VOYAGE OF TilE BEAGLE. falling very gradually from the commencement of the dorsal to the end of the snout, without any elevation at the nape. The head is one-third of the entire length. The lower jaw projects beyond the upper. The maxillary, which is broad, and cut quite square at its extremity, reaches to beneath the middle of the orbit. The suborbital has the margin entire and nearly straight. The upper jaw has a band of velutine teeth, broadish in front, but narrowing (the teeth at the same time becoming smaller and finer) posteriorly; with an outer row of not much longer, but considerably stronger, subconic teeth, placed at rather wide intervals; besides these, there are three or four teeth on each side of the anterior portion of the jaw, equally strong as those last mentioned, but more curved, the points reclining backwards, and set within the velutine band. In the lower jaw, there is the same band as above, but narrower, and with the teeth more in fine card than velutine, with stronger ones anteriorly, and along the posterior half of each side, where there are six or eight, standing nearly in a single row, very stout and curved, though scarcely longer than the others; outside the band, and on each side of the symphysis, there are three or four moderately strong subconic teeth, at short distances from each other, which may be considered as small canines. On the vomer and palatines, the teeth are velutine. The eyes are rather large, and placed high in the cheeks; their diameter is about one-sixth the length of the head : the distance between them equals one diameter and a quarter. The nostrils consist of two orifices, placed one before the other, a little in advance of the eyes, roundish-oval, the posterior one largest. The preopercle has the ascending margin not quite rectilineal, being slightly convex, and the angle at bottom rounded; the denticulations on the former are fine, but ve•·y perceptible; they become rather stronger and more distant at the angle, and a few of this character are continued along the posterior half of the basal margin. The opercle is armed with three points; the uppe1· one is triangulat·, small, and not very obvious ; the middle one is a moderately strong spine, about a quarter of an inch in length; the third is a little below this last, aud resembles it in form, but is much smaller. The membrane of the opercle terminates in a sharp angle, and is produced considerably beyond the middle spine. The line of separation between the opercle and subopercle is not visible. The gill-opening is large, and has seven rays. There are no scales on the snout or jaws, or between the eyes, or on the anterior portion of the suborbital; but they are present on the cranium behind the eyes, cheeks, (where they are numerous), and pieces of the gill-cover; the limb of the preopercle, and the lower margin of the interopercle, however, are nearly free from them. Those on the opercle a~·~ larger than th_ose .on the cheeks. All these scales, as well as those on the body, are finely Clhated, commumcatmg a slight roughness to the touch. The supra-scapular is represented by a larger and harder scale than the rest, of a semi-elliptic form, striated on its surface, and ob_soletely denticulated on the margin. The lateral line is parallel to the back, at between onetlurd and one-fourth of the depth. The pectorals are attached below the middle of a rounded form, the middle rays being longest, and about half the length of the heaci. The dorsal commences exactly above them, and occupies a space equalling half the entire length excluding the caudal. The spines are sharp, and moderately strong: the first is rather ~1ore than hal: th.e length of the .second, but scarcely more than one-tifth of the length of the third, wluch lH longest, equalhng more than half the depth of the body : from the third they decrease v.e ry gradually to th e nm· tl 1, wh 1' c h I·S of t1 1 e same length as the second · the tenth is again a ht.t le higher ·• this is followed bY th e so ft 1· ays, w1 H •e h are nearly even ' and about one-thu· ·d lug her than the last spine; the last two or three, however, are a little sl;vrter than the others. FISII. .') The anal commences in a line with the fifth soft ray of the dorsal, and ends a little before that fin : the second spine is strongest, and twice the length of the first : the soft rays are longer than those of the dorsal. There are a few minute scales between the soft rays of both dorsal and anal, to about one quarter of their height. The caudal is even, but may possibly have been worn so by use. The ventrals are directly under the pectorals, a little shorter than them, and pointed. CoLOUR.-" Varies much. Above pale blacki~h-green; belly white; fins, gill-covers, and part of the sides, dirty reddish orange: on the side of the back, six or seven good-sized snow-white spots, with not a very regular outline.-In some specimens, the blackish-green above becomes dark, and is separated by a straight line from the paler under parts.-Again, other specimens are coloured dirty 'reddish-orange,' and ' gallstone yellow,'• the upper parts only rather darker. But in all, the white spots are clear; five or six in one row, and one placed above. Sometimes the fins are banded longitudinally with orange and black-green."-D. Habitat, Galapagos Archipelago. This species, which is undoubtedly new, was obtained by Mr. Darwin at Charles Island, in the Galapagos Archipelago. As many specimens were seen, it is probably not uncommon there. It appears to be a Sen·anus, but its canines, if they can be so called, are very small and inconspicuous. Its naked jaws require it to be placed in Cuvier's first section of that genus, though much larger than most of the species contained in it, and rather differing from them in general form. In some of its characters, it would seem to make a near approach to Centropristes, between which and Sen·anus, there is undoubtedly a very close affinity. 2. SERRANUS GonEENSIS. Vat.? Serranus Gorcensis, Cuv. et Val. Ilist. des Poiss. tom. vi. p. 38•1., FoRM.-The general form approaching very closely that of the S. Gigas. Greatest depth onefourth of the entire length. Head rather less than one-third of the same. The diameter of the eye is one-fifth of the length of the head ; and the distance from the eye to the extremity of the snout is about one diameter and a quarter. The lower jaw is covered with small scales, but not the maxillary. The nostrils consist of two round apertures, the anterior one rather larger than the posterior, and covered by a membranous flap. The teeth in the upper jaw form a velutine band, with the outer •·ow in fine card, and two stronger and longer ones near the middle of the jaw on each side : below there is a narrow band of fine card, with stronger ones situated as above. The denticulations at the angle of the preopercle are well developed, especially two teeth which are much stronger than any on the ascending margin. The operc1e has three flat spines, the middle one longest and projecting further than the others; but the terminating angle of the n~embrane projects beyond this spine to a distance equalling the length of t In this o.nd in all other cases, Mr. Darwin has usccl lVerncr's Nomenclature of Colours, by Patrick Symc. |