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Show 1876.] A YOUNG DELPHINUS ALBIROSTRIS. 683 such a prominent feature in the Great-Grimsby specimen. Again, the sides are deep black over their whole extent; and if we divide the animal represented in BrightweU's figure into two equal parts by a middle vertical line, we find that the anterior border of the dorsal fin lies ^ an inch behind this line, which in the specimen itself would represent a distance of 7 inches*. In the Great-Grimsby Dolphin the middle vertical line passed through the dorsal fin, dividing it unequally, 2 inches lying in front and 8 inches behind it. Indeed, with the exception of the white snout, the figure of this animal given by Brightwell, and reproduced by Gray and Bell, presents not a single feature in common with the Great-Grimsby Dolphin. At first, not fully recognizing the fact that the authors I have mentioned in connexion with this species had borrowed their details from Brightwell, the original describer, and that any inaccuracy on the part of the latter would consequently be reproduced by the others, I was induced to consider the Great-Grimsby specimen a new species, and this in the face of many essential points of similarity between the skeletal peculiarities of it and D. albirostris. I have been deterred from doing this by m y attention being redirected by Prof. Flower to another and independent account of this species by Prof. Van Beneden f. This memoir I had at first been inclined to regard as of small value, so far as m y wants were concerned, seeing that it differed so greatly in its facts from the writings of the authors I have mentioned, and in whom, at the time, I was placing implicit trust, and also owing to a certain discrepancy which existed between Van Beneden's description and his accompanying figure, which made me doubtful as to the accuracy of the whole. But a more careful study of it, and looking at the plate more as a guide to the general outline of the body than as a representation of the markings, I was able to establish certain features in common between it and the specimen I have described ; moreover m y faith in Bright-well's description and figure has been much shaken. The drawing given by Van Beneden shows an animal somewhat blunter about the head than that represented by Brightwell, and with a slight approach to the hump close to the tail; but then the lower lip does not project beyond the upper, and the dorsal fin lies altogether in front of the middle vertical line, which corresponds to its posterior margin. The markings are also peculiar and do not in every respect agree with the accompanying letterpress description. * The animal measured 8 feet, whilst in tbe drawing it occupies a space of 7 inches; ^ an inch in tbe latter therefore would be equal to 7 inches in the specimen itself. But this does not agree with the accompanying letterpress, in which it is stated that from the tip of the nose to the dorsal fin the animal measured 3 feet 5 inches, and that the base of this fin was 11£ inches long. According to these measurements, therefore, 8 incbes of the fin must have been in front of, and 3 inches behind the middle vertical line. In reproducing the drawing Gray must have noticed this inaccuracy and adopted a middle course; for in his figure the dorsal fin lies immediately behind the middle vertical line; and this is the only respect in which his plate differs from BrightweU's. t Van Beneden," "Recherches sur les C6tac£s," Nouv. M u m . de l'Acad. R. de Bruxelles, t. xxxii. 1862. |