428 Dr. A. Guiither on some East- African Antelojies. 



and length than in Gazella Grantii, as will be seen from the 

 following measurements : — 



. ^- .2- 



inches, inches. 



Length of horn l■^ 13 



Circumference of horu at the hase .... 4^ 3| 



The question naturally arises whether the horns described 

 are those of younger individuals of Gazella Grantii] but 

 this must be answered in the negative, as the cranial portion 

 which has been preserved, of the male as well as of the female, 

 shoM'S that the animals were much older than our specimens 

 of Gazella Grantii, which are armed with horns of that large 

 size described and figured by Sir Victor Brooke. Moreover it 

 is not conceivable that fully matured horns like those obtained 

 by Mr. Thomson should be further develo]>ed into a shape 

 or size like that of Grant's antelope. Finally Mr. Thomson 

 informs me that the specimens were on the whole smaller than 

 Gazella Grantii, a statement which is confirmed by the less 

 width of the interorbital portion of the cranium. It is also 

 worthy of notice that the deep notch in the orbital margin of 

 the frontal bone, which is commonly observed in the skull of 

 gazelles and also in Gazella Grantii, is scarcely indicated in 

 the present species, for which I propose the name of Gazella 

 Thomsonii. 



Peters figured in the" ' Monatsberichte ' of the Berlin 

 Academy for 1879, p. 832, the skull of a male antelope not 

 fully adult, which he considered to be Gazella Grantii, but 

 which clearly belongs to a distinct species. It resembles 

 somewhat Gazella Thomsonii in the slight degree in which 

 the horns diverge from each other; but their annulated 

 portion is almost straight, and the annuli themselves are much 

 further apart, much fewer in number (about twelve), and 

 lower towards the hinder part of the horn. The base of the 

 bony core shows a bossy swelling, which is different from that 

 of Gazella Grantii, and entirely absent in Gazella Thomsonii. 

 This si)ecies may be called Gazella Petersii. 



Mr. Thomson has kindly supplied me with some further 

 particulars. His antelope is marked with a distinct, black 

 lateral band, the absence of which is characteristic of G. 

 Grantii. He found it in small herds, in country in which the 

 latter was abundant, the herds of the two species never ming- 

 ling with each other. He observed it over the range of 

 country from Kilimanjaro to Baringo and at various heights 

 under 6000 feet. According to our present knowledge, Gazella 

 Grantii would seem to occur further north and south than 



