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Show 246 MR. W. BATESON ON C O L O U R - [Mar. 6, His Excellency the Governor brought, I think, some 20 or 30 skins home. Messrs. Swanzy's agent, with w h o m I travelled home, was bringing some more which he thought might be commercially valuable, but which have turned out useless, and I obtained altogether 125. With these exceptions I never heard of any being brought from the Gold Coast. Very few of the Europeans in Accra to whom I showed them had seen them before, and I hear m y hunters declined to get any more; but when I go back to Accra I shall obtain some of the different varieties, now I know where to get them and also know that they are worth getting, for that the hilly countries of the two Akims and Ashanti-to say nothing of other districts-are full of them there can be no doubt. I think from what I could gather that these orange-marked ones are in tbe nature of an albino variation, for the marks vary in size and brilliancy, some of them being quite small, while others cover the whole skin. The habitat, food, and habits of these varieties are exactly the same as those of the black species, among which they are found. 5. On two Cases of Colour-variation in Flat-fishes illustrating principles of Symmetry. B y W . B A T E S O N , M.A., Fellow of St. John's College, Cambridge. [Eeceived March 6, 1894.] (Plate XVII.) The two cases of Variation here described are both examples of abnormal deposit of pigment in the skin of the normally unpigmented or "blind" side of Flat-fishes. Tbe two cases are unlike each other, but both are remarkable illustrations of the ways in which the phenomenon of Symmetry may be manifested and may contribute to the production of a definite result in Variation that is presumably sporadic. The first specimen is a small Brill (Rhombus Icevis), kindly sent to m e by Mr. Matthias Dunn, of Mevagissey, Cornwall. It is 9| inches long, and 6| inches wide in the widest part. The dorsal fin, the eyes, and other parts are normal in form and position. The only abnormality seen consists in the presence of a row of five spots of colour along the dorsal border of the body on the blind side, and of another row of three spots along the ventral border on the same side. The spots are on the body, central to the dorsal and anal fins, which are both of normal colour. The interest of the case lies in the remarkable symmetry with which the spots are distributed with reference to the longitudinal axis of the body. O n reference to the plate (Plate XVII.) it will be seen that each of the three ventral spots stands at very nearly the same transverse level as one of the spots of the dorsal series. The two anterior spots of the dorsal series have no representatives in the ventral series. This appearance of symmetry, so striking to the eye, is |