ttrSGt. SV. VBt. AKADEMlEl<rS SANDUNGAK. BAND 48. N:0 5. 



m 



in connection with the fact that in this arid region food must be scarce for these 

 animals. The buck killed there had chiefly fed on the leaves of an evergreen bush 

 which grew at a dry river-bed. 



The first two bucks killed at Lekiundu river (PI. XIV, fig. 5) measured both 

 of them when freshly killed 170 cm. in a straight line from the muzzle to the tip 

 of the tail, and the length of the tail corresponded to 26 cm. out of that. The 

 paler bucks from Chanler Falls were certainly not smaller, although I have no body 

 measurements of them. The buck from Njoro again which, as already mentioned, 

 was my smallest specimen has the basal length of its skull about 12 mm. shorter 

 than the type of 0. g. brighti. 



Condylobasal length of skull 



Basal length of skull 



Greatest breadth of skull 



Distance from orbit to tip of premaxillaries 



Least interorbital width 



Length of nasals 



Upper molar series 



A study of the cranial measurements recorded above shows that, with the ex- 

 ception of the specimen from Njoro, the other bucks are very much alike. The 

 greatest variation is found in the length of the nasals. One of the bucks from Le- 

 kiundu has long nasals 74 mm., one of those from Chanler Falls has also comparatively 

 long nasals 67 mm., but in the others they must be termed short. Skulls of 

 the typical Grant Gazelle from Kilimanjaro, often have rather long nasals measuring 

 more than 70 mm. It might thus appear possible that this should be a characteristic 

 of the typical race, and shorter nasals on the other hand of the smaller more northern 

 races. Some of my specimens are then intermediate in this respect as well. But it 

 must be remembered that the variation in this respect is rather great even among 

 the typical Grant Gazelles, and that fullgrown bucks of the latter race may be found 

 with the nasals measuring only little more than 60 mm. 



Short nasals stand in connection with a movable muzzle, and for a browsing 

 ruminant such an organ is of importance. The Grant Gazelles of the open plains 

 are grazers, but those of the thorn-bush are at least partly browsers. This may account 

 for the difference in the length of the nasals in different races if constant. 



It may be concluded from this that intergrading links between the typical G. 

 g. granti of the steppes of Central East Africa, and the paler and smaller races G. 

 g. brighti and G. g. lacuum of the arid regions further north can be found so that no 

 sharp limits can be drawn between them. The, as it seems, still incompletely known 



K. St. Vet. Akad. Handl. Band 48. N:o 5. 



22 



