134 EINAR LONNBERG, MAMMALS COLLECTED BY THE SWEDISH ZOOLOGICAL EXPEDITION ETC. 



Upper mesial length from occipital crest to tip of nasals . . . . 



Width of parietal flat area 



Greatest width at lambdoid crest 



Distance from postorbital process to lambdoid crest 



Greatest zygomatic width 



Width at postorbital processes 



Least interorbital width 



Distance from orbit to front end of naso-premaxillary suture . . 

 Distance from hind surface of m' to tip of premaxillary . . . . 



Length of m' 



Least width of skull between lambdoid crest and zygomatic arch 

 Least width of nasal surface of skull between the orbit and the 



apophyses above the canines 



Width across upper ends of the canine apophyses 



Width of nasal region on a level with anterior margin of canine 



alveoles 



representatives of P. chosropotamus have a much broader parietal area amounting to 

 about 12 "/o of the upper length of the skull, while the somewhat more northern race 

 P. ch. maschona has a narrower parietal area (amounting to about 6 "/o) than the 

 Kenia Bush Pig. In some respects the skull of this latter strongly reminds about 

 the West African Bush Pigs of the P. porcus group, especially by the great breadth 

 of the posterior nasal region (PI. X, fig. 3) between the orbits and the canine apo- 

 physes when compared with the anterior nasal portion in front of the apophyses 

 mentioned. The nasal surface is flat especially in its posterior two thirds. The canine 

 apophyses are very strongly developed in the boar(?) skull (PI. X, fig. 1 & 3), their 

 shortest anteroposterior diameter being 37 mm., and, although they hardly reach 

 the level of the nasal surface they are very broadly anchylosed with the lateral exo- 

 stoses of the snout so as to form a canal on the side of the upper jaw. This is the 

 more striking as the animal to judge from the condition of the teeth (PI. X, fig. 2) 

 is not very old. Such a coossification between the canine apophyses and the lateral 

 exostoses of the snout I have seen in, and also described from boar skulls of the P. 

 porcus group, but I have not seen it in other members of the P. choeropotamus group 

 than this one so that I do not know if it is a common occurrence there, which ap- 

 pears, however, hardly probable. 



The anterior portion of the zygomatic arch in the boar skull (PI. X, figs 2 & 3) 

 of the Kenia race forms a right angle towards the longitudinal axis of the skull, and 

 at the some time the anterior bony wall formed by this arch stands nearly vertically. 

 In the sow the latter is more sloping, but comparatively less than generally is the 

 rule in the P. choeropotamus group. 



