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Show 756 MR. F. DAY ON THE FISHES [Dec. 2, their crowns somewhat obtuse; teeth most developed on the blind side. Fins. Dorsal commences over the middle of the upper eye, its longest rays being in its middle, where they are three fifths of the length of the head ; posteriorly the fin terminates almost close to tbe root of the caudal fin, which latter is wedge-shaped. Anal similar to dorsal, but its middle rays not so elongated. Both pectorals with twelve rays, the left half as long as the head, the right one fourth longer than the left. Ventrals each with six rays, and one half as long as the pectoral. Scales cycloid on left, feebly ctenoid on the right side, none over the fin-rays except on the caudal. Lateral line with very slightly oblique descent above the pectoral fin, whence it proceeds direct to centre of the caudal. Gill-rakers short, spinate, and widely separated. Ceecal appendages two, moderately developed. Colours: right side brown, with a slaty tinge, darkest about the head ; a black blotch on the upper half of the pectoral fin ; vertical fins of a greyish slate-colour, the anterior dorsal rays being tipped with white; left side white. Habitat. A single example 9 inches long, from Megavissey, Cornwall, obtained and recognized by Mr. Matthias Dunn. Yarrell's example, a dried skin, had probably shrunk, causing it to appear more elongated than is natural. It is more closely allied to P. cynoglossus. PLEURONECTES FLESUS, Linn. The Flounder. Reversed examples were exceedingly numerous, and in one instance I saw a Flounder coloured on both sides. I would here draw especial attention to four abnormally coloured Plaice and Flounders in the Westminster Aquarium, all of which are white on the underside ; the eyes are normal; while the albinism I am about to describe has existed from the time they were received, neither increasing nor diminishing. In one (1) the dorsal and anal fins are white to a great extent, but in ratber an irregular manner; (2) the dorsal and anal fins are similar to no. 1, but the white has extended onto the sides of the body; (3) the white is rather more spread than in no. 2 ; (4) the caudal fin and most of the posterior half of the body are nearly white, whereas the anterior portion of the body is mottled. If, as suggested by A. Agassiz, the colours of these fish are affected owing to the eye, on what will eventually be the uncoloured side, passing over to the upper surface, leaving the eyeless side colourless, due to the controlling power of the nerve having become unable to act over the colour-cells, how, one would suggest, can this albinism be present in examples wherein both eyes are present on the dark side thus affected ? SOLEA VULGARIS, Quensel. The Sole. Small ones were common in the shrimp-nets at Weston ; and Mr. Mable writes me word from Weston (Sept. 13) that, " during the last few days, a large quantity of very fine Soles have been taken here. On inquiry I find they were caught about 30 miles down the Channel by two trawls from Cardiff; the gross weight was 10 tons, and the heaviest |