LÖNNBERG, MAMMALS FROM BRIT. E. AFRICA. 25 



tion differs from other skulls of Hyraxes representing the 

 same stage in which the fronto-nasal profile-contour is a^ 

 straight sloping line. In younger specimens the posterior 

 frontal region often is more or less arched, but there is no 

 such depression on a level with the anterior portion of the 

 orbit as in this skull. 



The anteorbital process of the lacrymal bone is triangu- 

 lär and rather pointed. In front of the lacrymal bone the 

 maxillary meets and forms a suture with the frontal thus 

 excluding the nasals from contact with the lacrymal. In 

 this respect the brucei-skuWs from the same locality differ 

 as in all of them the nasals meet the lacrymal more or less 

 broadly. On the other hand the nasals are excluded from 

 the lacrymal in the Dendrohyrax from the same locality. 



Another feature in which the present skull remarkably 

 differs from the two others from the same locality is the 

 shortness of the frontals. The mesial length of these bones 

 is decidedly shorter than the distan ce from the fronto- 

 parietal suture to the suture between interparietal and 

 the occipital. In the skulls of P. hrucei and those of the 

 Dendrohyrax from the same locality the mesial length of the 

 frontals is longer than the other distance, mentioned above, 

 in all specimens of corresponding age, and still more so in 

 the older ones. In younger specimens the frontal region is 

 relatively shorter when compared with the parietal region 

 than in older specimens. This feature is thus to a certain 

 degree to be regarded as a juvenile characteristic, but it 

 does not explain the difference between the ^rwcez-skulls and 

 the one now in question, especially as there are so many 

 other discrepancies. 



The basioccipital of this skull is comparatively very nar- 

 row its width at the suture with the basisphenoid being only 

 4,8 mm., while the same measurement in a hrucei skull of 

 the same stage is 6,8 mm., and already in a &rwm-skull of 

 stage III (also from the same locality) it is 5,5 mm., and in 

 stage VIII 7,5 mm. 



The dimensions of this skull together with those of a 

 likewise female 6r^/ce^-skull are recorded below. Both skulls 

 belong to stage VI, or the 6r^fC6^-skull perhaps intermediate 

 between stages V and VI as m^ is not quite up to the level 

 of the bone, although visible. 



