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Show 622 MR. O. THOMAS ON A N E W MUNGOOSE. [Dec. 3, 6. On a new Mungoose allied to Herpestes albicaudatus. B y O L D F I E L D T H O M A S , Natural History Museum. [Eeceived November 20, 1889.] (Plate LXII.) In a Monograph of the African Mungooses which I had the honour of laying before this Society in 18821, the extreme constancy in the size of the teeth in this group was pointed out, and the species were shown to be readily distinguishable by the relative dimensions of their posterior cheek-teeth, both upper and lower. While the more typical and specialized species, such for example as H. ichneumon, have their m 2 very small, and averaging in its greatest diameter less than 60 per cent, of the last premolar (\ff), one species, H. albicaudatus, forming the type of the subgenus Lchneumia, has this percentage 70 or more, and all the teeth are of a much less specialized and secant type than in the others. The species I now propose to describe is remarkable for having its posterior teeth even larger than in H. albicaudatus. The type specimen is a skeleton without a skin, which has been some time in the Cambridge Museum, and which the authorities of that institution have been good enough to transfer by way of exchange to the National Collection. This specimen is believed to have been collected by Mr. T. E. Buckley either on the Limpopo or in Zululand, but most unfortunately all definite record of its history has been lost. The most striking characteristic of the new species, which may be termed Herpestes grandis, is its large size and great length of limb. Its skull is only exceeded in length, and that very slightly, by one skull in the whole Museum collection of Mungooses, namely by that of the type specimen of H. galera robustus, Gray2, a thickly built, short-limbed form, whose long-bones are nearly 20 per cent, shorter than are those of H. grandis. Comparing now H. grandis with H. albicaudatus, to which alone it is in any way closely related, we find that that species occasionally attains dimensions approximately equal to its own, although the great majority of specimens, especially those from North-east Africa and Arabia3, are very much smaller. The real difference between the two lies in the form and dimensions of the teeth. Firstly, in H. grandis the canines both above and below are markedly longer and heavier than in H. albicaudatus, exceeding those in the largest available specimen of that species by at least 2 m m . in length above and 3 m m . below, and in thickness by 1 or 1| mm., although it is almost impossible to take the measurements exactly, owing to the absence of a distinct cingulum in this 1 P. Z. S. 1882, p. 59 et seqa. 2 See the above-quoted paper, p. 72. 3 Since m y Monograph was written, Mr. A. S. GL Jayakar has obtained examples of this species at Muscat. |
