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Show 112 MR. R. LYDEKKER ON A NEW [Feb. 6, 6. O n a Central African Ratel and Water-Chevrotain. By R. LYDEKKER. [Received January 6, 1906.] (Plate VII.*) I have lately been favoured with the opportunity of inspecting a number of skins and skulls of mammals collected by Major Powell-Cotton in Central Africa, among which two appeared worthy of bringing under the notice of the Society. In a letter sent to Mr. Rowland Ward referring to the localities of the specimens, Major Powell-Cotton states that they were all obtained on the "eastern fringe of the Ituri Forest to a point fifteen miles west of Mawampi and thence south-east to Boni, at elevations of between 2100 and 2950 feet above sea-level." The first specimen I have to bring to notice is an entirely black Ratel, represented by the skin and skull. The ordinary colouring of the Ratels-grey above and black beneath-is so characteristic not only of both the African and Indian representatives of the group, but also of various allied mustelines, such as the African Zorilla and Pcecilogale and the American Galictis, that it can scarcely be regarded otherwise than as a deeply ingrained attribute of the species in which it occurs, and one connected in some special manner with protective adaptation. Any departure from this type of colouring in animals of the group in question-unless, indeed, it wrere a mere instance of melanism-would seem therefore to imply an important modification in habits or surroundings. Now-although I have no justification for saying that the present specimen may not come under the category of a mere individual melanism-the conditions prevalent in the great Ituri Forest are manifestly very different from those of the open or bush-clad country in which Ratels are commonly found ; and they are, moreover, just the conditions which are conducive to the development of blackness in a species. Accordingly I venture to consider that Major Powell-Cotton's black Ratel very probably represents a distinct species, for which the name Mellivora cottoni may be suggested. A n all-pervading blackness, save for a few grizzly or tawny hairs on the upper part of the head, must be regarded as the sole distinctive characteristic of the species, as I can find no points in which the skull can be distinguished from that of the orclinay grey and black African Ratel. Not that this is a matter for wonder, since, so far as I a m aware, it is almost impossible to distinguish Indian from African Ratels by their skulls alone, or the fossil Siwalik species from its living Indian representative. In colour, length, and texture of hair the black Ituri Ratel may be likened to a Himalayan Black Bear. If the animal dwells in constant shade, the reason of its departure may not be far to seek, as I have little doubt that the greyness of the upper parts of ordinary Ratels is in some way connected with the play of sunlight upon this aspect. The specimen is represented in Plate YIT. * For explanation of the Plate, sec p. 113. |