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Show 1890.] SEXUAL CHARACTERS OF ARNOGLOSSUS. 543 Tho scales are extremly thin ; those of the upper side are larger ana have a single row of minute spines along the posterior edge, those ot tho lower side are smaller and are smooth with an entire edge without spines. The scales along the lateral line of the lower side are not pierced by a dermal tube and are not tubular; the lateral sensory tube is either rudimentary or absent on this side. On tho upper side the lateral dermal tube pierces a series of tubular scales as usual. Dr Giinther has made a mistake in stating that no author mentions a prolongation of fin-rays in the common British species of Scald-fash Couch, in his ' Fishes of the British Islands,' in his description ot the species says :-« The dorsal fin begins in front of the upper eye, and commonly is narrow at its origin, becoming wider at half its length, but in the example described several of the first rays were considerably lengthened into separate threads." The character thus mentioned is represented in Couch's figure, and agrees exactly with the condition I have described in m y larger female specimens. Couch cannot be eupposed to have confused the two forms, for he gives a separate description and woodcut of A. lophotes. Day also in his description of Arnoglossus laterna says " the dorsal commences on the snout, its first few rays being occasionally somewhat separated one from the other and a little elevated." The total number of specimens brought to m e in the beginning of last December and on which this paper is founded was 43. I determined the sex of all of these by opening the body-cavity. There were 30 males and only 13 females. As the specimens were collected indiscriminately, it is evident that the males are far more numerous than the females. The testes of the males are extremely small in comparison with the size of the ovaries in the females, and this fact is doubtless correlated with the numerical superiority of the males. The relations of the sexes in the common Sole, as shown in my treatise on that species, are quite similar. In size the sexes of A. laterna show no difference, the largest specimens both of males and females being 20*4 cm. in length, or just over 8 inches. I have examined those specimens of this species which are preserved entire in spirit in the collection of the British Museum of Natural History, with the following results. The specimen of A. laterna marked o, obtained by Mr. Murray in Kilbrennan Sound in the Firth of Clyde, is a female and resembles in all respects m y own female specimens. There are only two entire specimens of A. lophotes one obtained by Prof. Moseley off Cardiff in 1882, another sent by Prof. Doderlein from Palermo. Both are of the male sex. The first is 5| inches long, the second 6f inches. Both resemble my male specimens in all respects. In the Cardiff specimen the 4th dorsal ray is the longest, in the Palermo specimen the 5th. I have already stated that adult and full-grown individuals of the Scald-fish are abundant off the Devon and Cornish coasts up to the depth of 40 fathoms. Young specimens of all sizes from 1 cm. or even less up to 11 or 12 cm. are very abundant in Cawsand Bay, Plymouth Sound, at a depth of 2 to 6 fathoms. |