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Show 86 ZOOLOGY OF THE VOY .AGE OF THE BEAGLE. dotted m· l'k 1 some indication of the larger spot on the first three rays of the 1 e manner : a so dorsal: anal with the same dusky edging. . . . Obs. Of this species there are five specimens in the collectwn. The ~e~t m s1ze to the one described above, measures one inch seven lines in length, and resembles 1~ m every respect, excepting that the superciliary filaments are broader and longer, equalbng at least one diameter and a lialf of the eye. The colours and markings are exactly the same, only the fascial on the throat can hardly be discerned. No.3 is exactly similar in size, as well as in all its other characters, to No.2. Has the superciliary filaments equally developed. . . . . No.4 resembles Nos. 2 and 3, but is smaller, measurmg one mch _five lmes m_length. No. 5, the smallest of all the specimens, and measuring onl~ one mch three hnes, ~as the dark markings more developed, especially the angulated fasc1re on the throat, whiCh are almost as distinct as in the B. fasciatus : the spots beneath the dorsal assume th_e ap~earance of abbreviated transverse fascire reaching from the base of the fin to the median hne; and besides the three faintly indicated in the other specimens, there ~~e two others nearer the head, forming altogether a series of five. In tllis specimen the superciliary filaments are shorter, not exceeding the diameter of the eye. Habitat, Coquimbo, Chile. This species differs but slightly from the last, and both may hereafter prove to be mere varieties of the B. biocellatus; but it is desirable for the present to keep them distinct, as, though all found on the same coast, they are fro~ di.stinct localities on that eoast. Also the above five specimens, though varymg m the intensity of the markings, have all a ground colour quite different from that of the R.fasciatus, and a peculiarity of aspect immediately noticeable to the eye. Had they been found mixed with that species, the presence of the anal papilla might lead to the suspicion of their being the other sex ; but, under the circumstances, this seems hardly probable. They were all taken at Coquimbo. 7. SALARIAS ATLANTICUS. Cuv. et Val. &l.ario.s a.tla.nticus, Cuv. et Val. llist. des Poiss. tom. xi. p. 238. Two individuals of this species were obtained by Mr. Darwin at Porto Praya. They accord in all respects with the descriptions in the "Histoire des Poissons," excepting as regards the fin-ray formula, in which there is a slight difference observable; and in this respect they are also different from each other. The larger specimen, measuring three inches seven and a half lines in length, has the fin-ray formula as follows : D. 13/21; A. 24; C. 13; P.lo; V. 2. The other, two inches eleven lines in length, has one ray less in the spinous portion of the dorsal, and two more in the soft : D. 12/23; A. 24; &c.- FISH. 87 It may be mentioned that in this-species, as in some others, the last spinous ray in the dorsal is entirely invested by the membrane, and does not attain to the margin, so that in counting, it may be very easily overlooked. In Mr. Darwin's notes, it is stated that this S}>ecies bites very severely, having driven its teeth through the finger of one of the officers in the ship's company. Its two very long sharp canine teeth at the back of the lower jaw are well calculated to inflict such a wound. 2. 8ALARIAS QUADRICORNIS. Cuv. et Val.? Sn.larias quadricornis, Cuv. et Val. Hist. des Poiss. tom. xi. p. 243. pl. 329. Mr. Darwin's collection contains a species of Salm·ias so closely resembling the S. quadricornis of Cuvier and Valenciennes, that I dare not describe it as distinct. Yet it offers some slight differences as follows : The profile, instead of being merely vertical, presents a rounded and projecting front between the eyes, advancing further than the mouth (as in the S. giooifrons, Cuv. et Val.) The filamentous appendages are similar, but the superciliary ones are shorter than the diameter of the eye : the palmated ones at the nostrils consist of six or seven bristles. The occipital crest is hardly so much elevated; its height being not more than one-sixth or oneseventh the height of the head, and only one-third its own length. The height of the dorsal equals at least half the depth of the body; the depth of the notch above the thirteenth spinous ray is rather more than half its height. The fin-ray formula is- D. 13/21; A. 25; C. 13, &c.; P. 14; V. 2. The colour, as it appears in t~pirits, is nearly of a uniform olivaceous brown, with scarce any indication of vertical bands; paler on the abdomen. There are four or five oblique narrow whitish lines on the dorsal, but not very distinct; also two on the anal, more decided: these lines appear to have been bluish, and there are traces of the same colour about the head and gill-covers. In all other respects it accords exactly with the description in the "Histoire des Poissons," where it is added, in reference to colour, that this species is subject to much variation. Mr. Darwin's specimen measures five inches two lines in length. The number attached to it has been lost, so that there is nothing to shew where it was taken. It is probably, however, from the Keeling Islands, as there is in the collection, from that locality, another specimen, which I have little doubt of being the female of the one above noticed. This second specimen wants the nuchal crest, as is stated to be the case in the female of S. quadricornis. It is not full sized, measuring only three inches four lines in length, which may account for the proportions being a little different from those of the adult. The depth is one-sixth of the entire length, or rather less. The filamentous appendages resemble those of the first specimen, but the nasal ones have rather fewer bristles. In the form of the head, |