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Show 1890.] SOME BRITISH PLEURONECTIDiE. 41 by the discovery by the Rev. W. S. Green of a fish on the coast of Ireland which proves to be an adult specimen of the true A. grohmanni. Thanks to the kind help of the Marqnis G. Doria, Professor Doderlein of Palermo, and Professor Bellotti of Milan, I have materials before m e which place the question beyond any doubt, the result of m y examination being :- 1. That the two species are quite distinct, and well characterized by constant characters. 2. That both species are found both in the Mediterranean and on the British coasts, but are rarer in the latter area. 3. That the outlines of the figure in Proc. Zool. Soc. 1882, pi. 53, are taken from a British specimen of A. lophotes1, with the scaling and markings added from a Mediterranean A. grohmanni. The arguments brought forward by Mr. Day in support of his assertion that the two species are identical were the following:- 1. That he had received specimens of A. grohmanni from Prof. Giglioli of Florence, " which are identical with Prof. Moseley's fish." If that was the case, and if those specimens had the four or five anterior dorsal rays prolonged, and not the second only, then I have no hesitation in stating that those specimens were misnamed A. grohmanni. 2. That " the typical specimens of 34. lophotes are stretched or abnormally elongate skins." It is quite possible that these skins are a little more elongate than the fishes were whilst in the flesh ; but all the fresh specimens of A. lophotes have a more elongate body than adult and haifgrown specimens of A. grohmanni, as may be seen on comparing the figure of this species now given (Plate III. fig. A ) with the figure in P. Z. S. 1882, pi. 53. And in conformity with this greater prolongation of the body, the numbers of the fin-rays and transverse series of scales are larger in A. lophotes than in A. grohmanni. I have to add, however, that the smallest and youngest specimen oi A. grohmanni (2| inches long), which I received among those sent by Prof. Bellotti, has the body more elongate than older examples : a very common occurrence in the Pleuronectidae. 3. That the numbers of fin-rays show greater variations in Pleuro-nectoids than in other fishes; that, for instance, in the Lemon Sole (Solea lascaris) the number of dorsal rays varies between 65 and 89, and of the anal between 52 and 70 ! This is contrary to the observations of almost all ichthyologists (Mr. Day included) : the fin-rays of Pleuronectoids do not vary more than in other fishes with a similarly great number of fin-rays ; and the statement of so extraordinary a variation as the one referred to can only be accounted for by the observer having mixed up several species. The following table of the fin-rays of our specimens of A. lophotes and A. grohmanni will be, however, more to the point than any far-fetched comparisons of doubtful value. 1 The specimen when brought to the Museum by Professor Moseley immediately after its capture had lost not only the scales, but also the integuments; and of course every trace of colour was gone. |