1908.] SKULLS IN THE BRITISH MUSEUM. 937 



very narrow postorbital portion of the sknll. This is proved by the 

 following measurements obtained from specimen No. 69.10.24.47 

 in the British Museum, c? ad. from Zorilla, Abyssinia. The length 

 of this skull from the tip of the nasals to the occipital crest is 

 388 mm. The postorbital poi-tion has a length of 60 mm., but the 

 breadth of its flat area is only 24 1 mm. These differences in the 

 dimensions of the postorbital portion of the skull become still 

 more striking if they are expressed in percentages of the length 

 of the skull. In such a case the length of the postorbital portion 

 of the skiill of Ph. africanus will be found to be 13"4 °/q and the 

 width of its flat area almost the same, or 13"1 °l^ of the length of 

 the skull. The same percentages for Ph. celiani are respectively 

 15"4 °/q and 6'3 °/q. Ph. africanus has a comparatively narrow 

 interorbital space, which corresponds to only 30 °/q * of the length 

 of the skull. In Ph. celiani the interorbital region is a little 

 broader, so that it corresponds to 31"7 °l^ of the length of the skull. 

 The combined characteristics of the postorbital and interorbital 

 portions of the skulls of these two races give the impi-ession 

 that they are compaiutively longer than those of other races. 

 The skulls of these races are therefore at once distinguished from 

 others. Ph. massaicus has a comparatively long postorbital 

 region, viz. about 14 °l^ of the length of the skull, but as it is 

 very broad at the same time, its flat area measuring about 14*5 %, 

 and the interorbital region as well is very broad, being 38-8 °/^ of 

 the length of the skull, no confusion with other races is possible. 

 Ph. sundevallii has a somewhat shorter postorbital region, viz. 

 13*7%, and the flat area of the same is considerably narrower, 

 viz. ll"/^: at the same time its interorbital region is much 

 narrower than in Ph. massaicus^ so that the percentage expressing 

 its relation to the length of the skull, 32'3, resembles that of 

 Ph. celiani. In such a way these four races may be easily 

 distinguished from each other, if the material is derived from 

 adult males. 



Two Wart-Hog skulls in the British Museum from Angoni- 

 land (No. 8.2.14,1, S ad., and 8.2.14,2, 6 jun.) show some 

 afiinity to sundevallii. Their interorbital width is respectively 

 33-4 7„ and 32-1 % of the length of the skull (thus rather 

 similar in this respect to Ph. sundevcdlii), but the postorbital 

 portion is smaller than in Ph. sundevcdlii, its length being about 

 11-7 % and the width of its flat area 10-1 % of the length of the 

 skull in the adult. In the younger specimen the last-mentioned 

 dimension is still smaller (8-1 %)' ^^ always is the case with the 

 young ones, and cannot be considered. More material is needed 

 before anything can be decided about this Wart-Hog. It may, 

 however, be added that its choanse are rather wider, 36 mm. in 

 the adult, than in the typical Ph. sundevallii, 29 mm. 



Two other skulls of Wart-Hogs in the British Museum 

 one from Ukanga, Lake Nyassa (No. 91.5.9,3, S ad.) and 



* The interorbital measurements are al\va3's counted at the middle of the orbit. 



