AND AFFINITIES OF POTAMOGALE. 3 



It is exactly in this position that Mr. Du Chaillu's name of Potamogale stands : it 

 has thus precedence over Gray's name of Mythomys ; and the laws of natural-history 

 nomenclature compel us to accept it. The synonomy of Mr. Du Chaillu's animal will 

 accordingly stand as follows: — Potomogale (prov. gen.) velox, Du C\\&\\\\x,=.Cynogale 

 velox, Du Chs.\)l\x,-=MytJiomys velox, Gray (gen.). 



External Characters and Teeth. 



Potamogale velox (Plate I.) is somewhat larger than a stoat ; it has very much the 

 aspect of a small otter, but is rendered especially striking by its broad, almost spatuli- 

 form muzzle and its very large laterally compressed tail. Both fore and hind limbs are 

 short and nearly equal to one another in length. The body is clothed with somewhat 

 coarse but soft hair, which projects from a shorter dense coat of very fine silky hairs ; 

 and the same kind of clothing covers the base of the tail as far as an oblique line which 

 terminates below at about an inch behind the vent, and above at about an inch still 

 further back ; the whole of the rest of the tail is covered with short, coarse, closely 

 appressed hairs. The sides of the upper lip give origin to stiff bristle-like whiskers, 

 which commence at the point of the nose, and continue to be borne as far back as a 

 point nearly vertically over each angle of the mouth, increasing in length and thickness 

 from before backwards ; the most anterior are short and incline forwards, and they then 

 acquire more and more of a backward direction until we find the most posterior 



Fig. 1. 



Hair from the body of Pofamoc/ale velocc.—k, one of the longer hairs, magnified about ten diameters ; B, a por- 

 tion of one of the shorte'r and ner hairs, magnified about 40 diameters to show its structure ; «', a piece 

 from near the middle of the narrow basal portion of A ; a\ from the middle of the broad terminal lamina : 

 and a\ the terminal portion of the lamina: the last three magnified about 40 diameters. 



attaining a length of nearly two inches, and inserted so obliquely that their tips are 

 nearly an inch behind the ears; a few stiff bristles also arise from the cheeks, a little 

 below and in front of the ears. The underside of the muzzle is clothed towards its 



