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Show 136 ZOOLOGY OF TilE VOYAGE OF TIIE BEAGLE. torals reach to the veotrals, and are contained about once and two-thirds in the length of the head. Caudal deeply forked; the lower lobe a little longer than the upper one: the base a ears to have been covered with minute scales. Above the pectorals is a thin membrana. c~~us lanceolate scale, more than half the length of the fin ~ a somewhat similar scale in the axillre of the ventrals, but shorter in proportion; another below those fins. CoLoun.- " Body silvery: dorsal scales iridescent with green and copper: head greenish: tail yellow."-D. A second specimen agrees with the above in form, but is smaller, measuring only 7t inches. The colours, when recent, according to Mr. Darwin's notes, were as follows :-" Scales silvery iridescent; back especially greenish; caudal fin yellow : remarkable for a circular dark green patch behind the gill-cover."-D. Habitat, Bahia Blanca. This species was caught by Mr. Darwin in the net, on a sandbank, at Bahia Blanca. It is well characterized by its strongly-pectinated scales, and does not appear to have been noticed by authors ; though it would seem in that respect to have some affinity with the Clupeafimbriata of Bowdich.* ENGRAULIS RINGENS. Jen. E. capite compresso, gmndiusculo, q·uartam partem longitudinis totius cequante: rosl1' 0 acuto, ufltm maxillam superiorem mediocriter prominulo ; mandibuld angustd, dentibus lateralibus (ut etiam in maxilla) minimis: co1pm·e compresso: pinnis ventmlibus infm, vix ante, initium pinnce dorsalis exm·ientibus : squamd longissim a membranaced super pinnarn pectoralem reb·ot·sum pmductd. D. J5; A. l9; C. 19, &c.; P. 16; V. 7. Lor\G. unc. 6. FoaM -Closely resembling the common Anchovy, but the head decidedly larger and longer, being one-fourth of the entire lcngth.t Eye larger, but bearing an equal proportion to the size of the head; also rather nearer to the tip of the snout in consequence of this last not being so acute and much produced. Lower jaw rather narrower, from the greater compression of the head and body. Maxillary, and its fine scrratures on the edges for teeth, similar. The depth of the body is ab()ut one-sixth of the entire length. The dorsal commences at the middle point of the length, reckoning this last to the base of the caudal fork, and terminates a little before the commencement of the anal : the first ray is not half the length of the second and third, which equal three-fourths of the depth : the fifth and succeeding rays become gradually shorter than those which precede. The first ray in the anal is likewise very short, and scarcely one-third of the next following. The ventrals arise almost directly under the first ray of the dorsal, being scarcely at all in advance ; when laid back, they do not reach half-way to the anal. Above the pectoral is a long membranaceous scale equalling, or very nearly, the fin itself. • Excursions in Madeira, p. 234, fig. 44. t In the E. encltra8icholus, it is hardly one-fourth of the length, excluding caudal. FISH. 137 CoLoun.-Not noticed in the recent state. In spirits, it appears silvery, with the back and upper part of the sides deep dusky blue, the two colours separated by a well-defined line. Habitat, Jquique, Peru. This ·is probably an undescribed species of Engraulis; nor am I aware that authors have hitherto noticed any from tllf~ west coast of America. Mr. Darwin obtained two specimens which are precisely similar to each other. The species closely resembles the common European Anchovy,* differing principally in its larger head, anrl more backward ventrals in respect to the dorsal. FAMILY.- PLEURONECTIDlE. M1·. Darwin's collection contains individuals of five species belonging to this family, besides the drawing of a sixth; but the specimens brought home are dry, and badly preserved. Two appeal' to have been previously noticed; but it i.s difficult to pronounce upon the other three with certainty, neither do they admit of being very accurately described. These last, therefore, I shall not venture to name, but merely point out a few of their principal characters, adding the localities whence they were obtained. The species, of which there is a drawing, I conceive to be certainly new; and as its characters are very distinguishable, I shall name it in honour of the gentleman, one of the officers of the Beagle, by whom the drawing was made. 1. PLATESSA 0RBIGNYANA. Val.? Platcssa Orbignyana, Val. in D'Orb. Voy. dans l'Amer. :Merid. Atl. Ichth. Pl.l6. fig.l. FonM.-Oval; greatest breadth two and a half times in the length. Ey~s on the left side, ncar together, and equally in advance. Teeth in a single row, sharp-pomtcd, moderately strong, rather widely separate: posterior extremity of the maxillary c~t nearly square. ~~rsal commencing in a line with the eyes, and leaving a space between 1t and the caudal. lhc .lateral line takes a sweep over the pectoral. Upper or eye side of the body slightly rough, With tbc scales finely ciliated; under side smooth, the scales on this side not ciliated. CoLOUR.-" Above dirty reddish brown; beneath faint blue: iris yellow."-D. Length 8 inches 9 lines. Habitat, Bahia Blanca, where it is said to be plentiful. This species agrees so well with the figure of t~e ~· ~rbignyana in D'Orbigny" s Voyage, that I have little hesitation in constdenng 1t the same,-but as • I am indebted to Mr. Yarrcll for tho loan of a specimen of our common Anchovy for comparison. T |