622 MR. O. THOMAS ON A NEW MUNGOOSE. [DcC. 3, 



6. On a new Mungoose allied to Herpestes albicaudatus. 

 By Oldfield Thomas^ Natural History Museum. 



[Received November 20, 1889.] 



(Plate LXII.) 



In a Monograph of the African Mungooses which I had the honour 

 of laying before this Society in 1 882 \ 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^ very small, and averaging in its greatest diameter less 

 than 60 per cent, of the last premolar (p^), one species, H. albicaudatus, 

 forming the type of the subgenus Ichneumia, 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 col- 

 lected 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. Gray', 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 Arabia^ are very much smaller. 



The real difference between the two hes in the form and dimensions 

 of the teeth. Firstly, in H. graiidis the canines both above and 

 below are markedly longer and heavier than in E. albicaudatus, ex- 

 ceeding those in the largest available specimen of that species by at 

 least 2 mm. in length above and 3 mm. below, and in thickness by 

 1 or li mm., although it is almost impossible to take the measure- 

 ments exactly, owing to the absence of a distinct cingulum in this 



1 P. Z. S. 1882, p. 59 et seqq. 

 ^ See the above-quoted paper, p. 72. 



^ Since my Monograpli was written, Mr. A. S. G. Jayakai- has obtained 

 examples of this species at Muscat. 



