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Show 84 ZOOLOGY OF TilE VOYAGE OF THE BEAGLE. ). BLENNECHIS FASCIATUS. Jen. PLATE XVII. Fig. 1. B. jlavescens, fusco-variatus; maculis t1·ibus infra pinnam dorsalem, et una in pinnce ipsitts anticam paTtem, nigris, subocellatis: dentibus maxillaribus supra circite1· viginti quatuor, subtus triginta ; caninis nullis : tentaculi.s palpeb1·alibus duobus, pm·vis, sttbpalmatis: pinnd anali ltaud ultra dorsalem extensd. D. 13/16; A. 20; C. 13, &c.; P. 14; V. 2. LoNG. unc. 2. lin. 4. FoRM.-Body much compressed behind: the depth one-fifth of the entire length : head rather less than one-fourth of the same. Snout blunt and truncated ; the profile nearly vertical; the eye placed just within the angle formed by this last with the line of the crow11. Diameter of the eye one-fourth the length of the head ; distance between the eyes half a diameter ; the interocular space very slightly concave, with a double row of mucous pores rather widely separate, but without any lines or sculpture. Similar mucous pores are thinly scattered over the occiput and the front of the snout, as well as beneath each eye. Above each eye is a short slightly palmated filament not exceeding in length the diameter of the eye: also an extremely minute one at each nostril. Mouth reaching to beneath the eyes. Teeth not extending the whole length of tl1e jaws; fine and close-set, with the points of those at the sides, more especially in the lower jaw, reclining backwards; the number above twenty-four, below thirty: no canines. Gill membrane fastened at bottom, the slit at the sides not descending below the pectorals. The dorsal commences at the nape, and extends nearly to the caudal, with which, however, it is not connected: it is slightly depressed or notched above the twelfth and thirteenth rays, beyond which it is again elevated to the height of the anterior portion. The anal does not approach quite so near the caudal as the dorsal, but the difference is trifling: the last ray in both fins is united by the membrane to the fleshy part of the tail. Caudal rounded, with the greater part of the principal rays slightly divided at the tips. Pectorals broad, and not quite equal to the head in length. Ventrals short, not more than half the length of the head, or a little less than one-eighth of the entire length: they appear to consist of only two rays, but on dissection there will be found three soft rays with a short spine closely adhering to the first of tl1em; the third soft ray is slender, and also adheres to the second. The anterior portion of the lateral line takes a sweep over the pectoral, and is very distinctly marked by a close series of short elevated mucous tubes between two rows of pores ; but the res~ of the line is only faintly traced out by nine or ten slender depressed tubes at long intervals, w1thout any accompanying pores. Cotoun.-(Jn spirits.) Yellowish ground; the upper half of the sides very much mottled, and cloud~d with fuscous; three spots darker than the rest, arranged longitudinally beneath the postenor half of the dorsal, and having a subocellated appearance, the last the largest, and also the mos.t dist~nct of the three: from the median line there are eight or nine descending fascire, alternatmg w1th the same number of oblong lanceolate spots: the throat is marked with three angulated transverse dark fasciro: cheeks and gill-covers with small spots. A large black spot on the first three rays of the dorsal fin, which is covered all over with ~>maller spots, as are also |