196 MR. OLDFIELD THOMAS ON THE [NoV. 15, 



in Sus and Potcmiochoerios, while the formation of the parietal 

 region and the characters of the last upper premolar are peculiar 

 to itself. Of ordinary pigs it shows no special aifinity whatever 

 with its geographical ally Potamochoirus, for it has neither the 

 characteristic rugosity of the muzzle, the specialised lower canine 

 section, nor the simple basisphenoid of that genus. In these 

 latter respects it agrees more with the Sus verrucosus group and 

 with the Babirussa, but even with them the agreement seems to 

 be rather in the common i-etention of primitive characters than 

 any real near relationship. 



With regard to geographical distribution, I have little doubt 

 that this animal will be found to occur not only in the East- 

 African forests already mentioned, but throughout the great 

 Congo forest, just as Boocercits does ; and Mr. G. L. Bates, the 

 well-known West- African collectoi', even tells me that as far west 

 as the upper waters of the Ja River, French Congo, the natives 

 speak of a large black forest-pig, which can hai-dly be anything 

 else but the present form. 



Its habitat being therefore so typically a forest one, I have 

 proposed to call the genus Hylochoerus, while the species is 

 termed meinertzhageni (cf. 'Nature,' vol. Ixx. p. 577, 1904), in 

 honour of the sportsman to whose efforts and generosity the 

 National Museum owes this interesting and important accession. 



The following is a more detailed description of the specimens 

 before me : — 



Body covei-ed thickly and uniformly with black bristles about 

 3-8 inches in length, oval in section, about 0*4 mm. in the 

 greater and 0'3 mm. in the lesser diameter. Chest and groins 

 with a certain nvimber of whitish hau"s. No evidence as to the 

 existence of a mane, nor are the ears or tail preserved in either 

 of the specimens. 



The skull, as may be seen by the accompanying figures 

 (Pis. XI Y. and XV.), has the general pi^oportions of that of Stis or 

 Potamochmriis^ not the veiy peculiar ones found in Phacoclio&rus. 

 The crown is very broad, concave above, pai'allel-sided, the breadth 

 between the intertemporal fossse approximately equalling that 

 between the orbits, a state of things very different from that found 

 in any other recent pig *. Occipital surface broader and lower than 

 in other genera, concave, its median line with a sharply defined 

 raised ridge running from the top of the foramen magnum to the 

 centre of the occipital crest ; no such ridge is present in other 

 genera. Sides of nasal region sloping smoothly outwards, as in 

 Phacochoerus, without any tendency towards the sharpened and, in 

 old animals, rugose edge characteristic of Potamochoirus, though it 

 should be remembered that the only specimen showing this part 

 is rather immature. Socket of canines with a prominent longi- 

 tudinal crest above, probably much more heavily developed in old 

 age. Zygomata broad and heavy, thickened and strongly convex 



* In the Pikermi Sus erymanthius, however, the proportions of the crown are 

 siugulai'ly like those of Si/lochoerus, widely as it differs in every other respect. 



