174 BINAR LONNBERG, MAMMALS COLLECTED BY THE SWEDISH ZOOLOGICAL EXPEDITION ETC. 



The dorsal stripe is quite absent in one of the specimens, in another it is rather 

 weakly represented on the posterior portion of the back, in a third it extends from 

 the middle of the back to the sacral region, and in the fourth from above the shoul- 

 ders to the loins. 



The black marking on the cannon-bone is only slightly developed on the fore 

 legs, in some instances there is only a black shadow streak, in others it deserves the 

 name of a black spot but not very large. On the hind legs below the hocks one of 

 my specimens is shaded with black on the outside down to the false hoofs. Another 

 has a rather big black blotch 15 X 4V2 cm. on the outside of the cannon bone below 

 the hocks. In the two others this portion of the hind leg is only more or less faintly 

 shaded with black. This variability is of interest especially as these markings re- 

 mind about the condition of other species. 



The following cranial measurements of my specimens prove my best bull to be 

 larger than Hollister's type, but not to such a degree as to cause any doubt as to 

 the racial identity. 



Condylobasal length 



Greatest breadth of skull 



From orbit to tip of premaxillary 

 Least interorbital breadth . . . . 



Length of nasals 



Length of upper molar series . . . 



Length of horns 



Spread at points 



All these specimens are fully adult specimens with rather strongly worn teeth. 

 The smallest and the biggest cow were in company when shot. The individual varia- 

 tion in size is thus rather great, as usually is the case with those animals the growth 

 of which is continued through several seasons which are apt to offer different con- 

 ditions of life. With regard to animals which live in such a country as these Oryx 

 Antelopes do, this fact is quite easy to understand, because a long and severe drought, 

 which is nothing rare there, may make the pasture extremely scanty and of bad 

 quality. This naturally results in starvation for the antelopes, and a stunted growth 

 of the young animals, while those which grow up during a period of favourable rains 

 get abundance of food. 



We met with Oryx Antelopes of this kind on the acacia steppe round the tribu- 

 taries Luazomela, Itiolu, and Lekiundu rivers to Guaso Nyiri. In some places they 

 wery quite numerous in this country. They were also seen on the northern side of 

 Guaso Nyiri but were not so numerous in the thornbush there as on the steppe on 

 the southern side. 



They occur sometimes single or two or three together, oftener in small herds 

 containing from five to a dozen or more. If the animals are common in a locality 



