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Show 750 ON ARNOGLOSSUS LOPHOTES AND A. GROHMANNI. [Dec. 19, in the Lemon Sole-clearly indicating that such a variation in number is well within such as is normally perceived in European species which visit the British coast. This deviation in the number of rays is consequently an insufficient reason for constituting A. lophotes a species; and it must be regarded as a synonym of A. grohmanni, which can now be recorded among the wanderers to our shores. I now come to the consideration of the statement that this Cardiff example " establishes the validity of Dr. Giinther's classification of this fish (Lophotes arnoglossus) as a distinct British species." I have only seen Dr. Giinther's remarks that "it is not at all improbable that these three specimens (skins from Yarrell's collection) really are British" (Cat. iv. p. 418); but in his 'Introduction to the Study of Fish,' p. 556, 1880, he merely places one species of this genus, Arnoglossus laterna, as extending to the south coast of England. After Dr. Giinther had recorded the skins as forming a distinct species, Couch was, I believe, the first and the last author who admitted Arnoglossus lophotes, Giinther, to be a British form. He gives as his reason that " these same examples [the three skins] were examined by myself at M r . Yarrell's house, at which time I made a note of its being that gentleman's opinion that they formed varieties or monstrosities of the Megrim or Scaldfish (Arnoglossus laterna) ; but that they appeared to m e to differ considerably from other examples of the last named" &c. (Fish Brit. Isles, iii. p. 179). He says that he "judged them to be a species new to Britain; but from whence they were procured did not appear." Couch considered that he had seen an example of the same species among a collection made by Lieutenant Spence, of the Royal Navy, at Plymouth ; and it was on this supposition that he introduced it into his work. The only doubt is, whence Yarrell's skins which formed the type of Arnoglossus lophotes were derived. In the last edition of his work, vol. i. p. 645, he records the possession of a Mediterranean specimen of the Megrim, Arnoglossus laterna, and tells us that the lateral line at its commencement rises higher than in his figure of the British M e grim. I think that this will account for one example of the three skins in the national collection, which has the curved portion of the lateral line abnormally elevated, as shown in Couch's figure. But as this specimen is one of three of certainly the same species, all forming types of A. lophotes, Giinther, I think we are justified in concluding that all may be Mediterranean specimens, especially as we have no evidence whatever of their being British. This would lead to the inference that they would probably be Mediterranean specimens ; and certainly the example obtained at Cardiff gives us every reason to suppose that it is.4. grohmanni, identical with the types of A. lophotes, Giinther. The figure (Plate LIII.) is taken (natural size) from the example of this fish obtained by Prof. Moseley in the British Channel, and now in the British Museum. It therefore represents an unquestionably British specimen of Arnoglossus grohmanni. |