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Show 162 ZOOLOGY OF THE VOYAGE Ol!' THE BEAGLE. rather the longest; neither can I discern any teeth on the palatines, though there is a patch of very minute ones in front of the. ~omer. . . That this species really belongs to Apltntu, wou_ld seem mdiCated not mer~ly by the aggregate of its external characters, but by the mternal structure also.' which was examined in one of the two specimens brought home by Mr. Darwin, and found conformable to what is stated by Valenciennes, in this respect, of the .A. Urvillii. The stomach is large, with four very distinct crecal appendages, and there is no air-bladder. The A. undulalus, which I have so named in reference to the undulating longitudinal lines on the sides, is very Cypriniform in general appearance, and not altogether unlike the common minnow, Cyprinus Plwxinus. 2. APHRITIS POROSUS. Jen. A. brevior: pallide olivaceus, laleTibus fasci is transversis obsoletis nigt·icantibus; pinnis omnibus brunneis : maxilla inferim·e, et li·mbo preoperculi, poris conspicuis circiter novem, suborbitalibus circitet· quinque, seriatim dispositis. D. 8-25; A. 1/22; C. 14, &c.; P. 23; V. I/5. LoNG. unc. 2. lin. 5. FonM.-Not so much elongated as the last species: the depth rather more than one-sixth of the entire length, and the head only four times in the same. Also distinguished by a row of large mucous pores on the lower jaw, passing upwards posteriorly, and continued along the limb of the preopercle : the number of these pores on each side is nine or ten : a row of similar pores, amounting to about five, passes backwards from a little above the end of the maxillary beneath each eye. In other respects, the form is similar to that of the last species, excepting that the interval between the second dorsal and the caudal is only one-eighth of the entire length, in consequence of the body being less elongated. CoLOuR.-( In spirits). Back and upper half of the sides, olivaceous brown; beneath silvery. No very obvious markings; but traces may be seen of six or seven transverse dusky fascire, reaching from the back to a little beneath the lateral line, which were probably more distinct in the recent state. All the fins brownish; the dor,;al a little powdered with dusky specks. The fourth and fifth rays of the ventrals are white, and appear to have been always of a different colour from the rest of the fin. Habitat, Coast of Patagonia. This appears to be another new species of Aplu·itis, taken by Mr. Darwin on mud-banks, in Port Desire, central Patagonia. It is very closely allied to the A. ttndulatus, but, I conceive, certainly distinct. There is but one specimen in the collection. FISH. 163 FAMILY.-SCORP ..EN IDlE. APISTUS --- ? Mr. Darwin's collection contains a species of this genus procured in King Geo~ge's S_o~nd, New Holland, which, from the bad state of preservation of the specime~, It IS scarcely possible to identify with certainty. Possibly it may be new, as It does not seem to accord very exactly with any of those described in the "Histoire des Poissons ;" but I shall not consider it such, nor do more than point out a few of its more obvious characters. It is not determinable, whetlter it was originally one of the naked species of this genus, or whether the scales have been rubbed off, but probably the former. The suborbital and preopercular spines arc strong, and considerably developed: the former reaches back further th~n the. maxillary, and nearly to the posterior part of the orbit, and has another very small spme at Its base. The lower jaw advances beyond the upper. The head is about one-third of the entire length. The eyes are large, their diameter being contained about three and a half times in the length of the head. The dorsal commences in a line with the ascending margin of the preopercle. The first spine is half the length of the second; the second is a little shorter than the third, which is longest, and equals two-thirds of the depth of the body; the fourth and succeeding ones decrease very gradually; the soft portion of this :fin is a little higher than the hinder part of the spinous. The first anal spine is rather more than half the length of the second, which is the strongest of the three, though not much longer than the third, The pectorals are rather pointed, and a little shorter than the head. The ventrals are attached a little behind the pectorals, and are not very much shorter than those fins. The following is the fin-ray formula: D. 13/9; A. 3/6; C. 11, &c.; P. 11 ; V. 1/.s. Length 4 inches 6 lines. The species to which this approaches nearest would seem to be the A. niger of Cuvier and Valenciennes ; but there is no appearance of the small elevations on the skin resembling hairs, which those authors mention in their description of this last, and, on the whole, I am inclined to consider it as distinct. AGRIOPUS HISPIDUS, p. 38. Notwithstanding what I have advanced in regard to this species, further consideration has inclined me to suspect, that it may prove ultimately only the young of the A . Peruvianus. In that case, however, it would appear that the absence of vomerine teeth can only be assigned as a character of this genus in the adult state. |