8 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 56 



middle and about 50 mm. wide near the posterior end, are reduced 

 to narrow streaks from 8 mm. wide in the middle to 10 mm. wide 

 near the posterior end. The stripe is nowhere pure blackish brown, 

 as in beisa, but is everywhere mixed with hairs of the body color. 

 In beisa the lateral stripe sharply divides the area of color of the 

 side from the white of the belly. In the Laikipia animal the white 

 below the stripe is suffused with the darker color of the side, the 

 stripe really passing across the lower edge of the side color nearly 

 an inch above the white of the belly, which gradijally becomes purer 

 below it, instead of being sharply defined. The dorsal stripe is also 

 less distinct. 



The markings of the head differ somewhat from a head of beisa 

 also. The black stripe passing through the eye extends down and 

 forward nearly to the corner of the mouth, and the face patch is 

 broader at the lower end, the two black areas thus reaching within 

 less than 25 mm. of each other, much after the pattern of coloration 

 in 0. callotis. In another example, a mounted head in Mr. White's 

 collection, also from Laikipia, the eye stripe passes down to join the 

 black throat stripe. This head, as well as another head skin, ac- 

 companied by the skull, presented to the Museum by Mr. White, 

 agrees with the type skin in the general peculiar color. 



Skull and teeth. — Skull as in O. beisa, but with much larger teeth ; 

 molars nearly as broad as long; lacrymal vacuities greater. 



From a Taveta specimen of O. callotis the skull of this new 

 species differs in many particulars. It is smaller and much nar- 

 rower in front of orbits. Ends of premaxillse square, very dif- 

 ferent from the tapering, pointed ends in callotis. Median palatal 

 notch shallow, not reaching to plane of last molars. Upper tooth 

 row much shorter, about equaling the length of last five teeth of 

 callotis; molars about as broad as long. Lacrymal capsules much 

 less inflated. Audital bullae small and flattened ; alisphenoids smaller. 



Measurements. — The skull of an adult male (No. 155413) from 

 the type locality measures : Condylobasal length, 356 millimeters ; 

 greatest breadth, 152; muzzle to orbit, 219; least interorbital breadth, 

 103 ; length of nasals, 142 ; upper tooth row, 105 ; length of horn, 

 685 ; spread at points, 210. 



Remarks. — ^This new oryx apparently needs no special compari- 

 son with O. b. gallarum. From O. callotis it differs in its lack of 

 ear tufts and the position of the parting of the hair on the back. 

 These and other general characters place it in the beisa group. The 

 •skull differs so greatly from a skull of O. callotis that it would cer- 



