EINAR LÖNNBERG, THE GENUS POTAMOCHCERUS. 11 



long bristles. On the forehead is a sharply defined black 

 patch which mesially extends forwards someAvhat in front 

 of the eyes. In front of this the whole snout is (in contrast 

 to the condition in P. porcus) whitish only with the sensory 

 bristles black. Behind the black frontal patch the bright rufous 

 general colour begins and extends as far back as the skin 

 reaches. A narrow, piire white dorsal mesial band begins 

 just behind the ears. It is formed by hair which as far as 

 this head skin reaches are not visibly prolonged above the 

 surrounding rufous hair. The ears are externally black 

 with yellowish and finally white upper margin. The tuft 

 consists partly of white, partly of black hair. A black cheek- 

 stripe is bordered above by a whitish tuft below the eye, 

 and on the lower side by the white whiskers. On the throat 

 rufous and black hair are mixed. 



For the present it is impossible to say how this sub- 

 species of the Red River Hog is geographically distributed. 

 It might, however, be more or less nearly related to a 

 comparativel}^ narrowheaded River Hog from the interiör of 

 the Togo-land. In the latter I have found the parietal flat 

 area to be about 6,7 % of the upper mesial length of the 

 skull. 



Potamocliceriis porcus albifroiis Du Chaillu. 



The skull characters by which P. p. uhangensis is recog- 

 nised are mentioned above, and also that it differs in colour 

 from P. porcus (and P. p. pictus) by its white snout. It 

 remains to find out in which respect it differs from Du 

 Chaillu's P. albifroiis. The latter is said to have the general 

 colour of the head white w^ith »a triangulär black space, 

 the base between the ears and ending in a point on the 

 median line about three inches below the eyes». »Face — 



— with a black w^arty prominence on each side halfway 

 between the nose and the eyes, and in front a circular black 

 line extending nearly to the angle of the mouth; nose black»; 



— — »eyes surrounded by a white line three fourths of 

 an inch wide, of the general color of the head interrupted 

 by bay opposite the ears; from the ears a black stripe mixed 

 with rufous hair coming down the cheeks; whiskers long, 



