258 NATURAL SCIENCE. 



JUNE. 



Waller's Gazelle to generic rank under the title Lithocranius,^ a 

 course which was fully justified, and has been since adopted by Mr. 

 Thomas and myself. 



Waller's Gazelle, I should add, appears to extend throughout 

 Somali-land down to the Tana River, where Sir John Willoughby 

 and his companions found it "numerous."^ It also occurs, though 

 rarely, in the Kilima-njaro district. 



In Northern Somali-land, Captain Swayne tells us the Gerenouk 

 is one of the commonest and most widely distributed Antelopes, and 

 is readily distinguishable by its long neck, large giraffe-like eyes, and 

 long mobile muzzle. It is more of a browser of bushes than a grass- 

 feeder, and may be sometimes seen standing on its hind legs with its 

 neck extended, and its fore feet lodged against the trunk of a tree in 

 order to get at the tender shoots and young branches. 



The Gerenouk is found all over Northern Somali-land in small 

 families, never in large herds. It is generally met with among 

 scattered bushes, in ravines, and on rocky ground. Its trot is 

 awkward, looking like that of a camel. This Antelope seldom 

 gallops, and its pace is never very fast. 



Nearly allied to the Gerenouk, and in some respects intermediate 

 between that form and the typical Gazelles, comes the second newly- 

 discovered Antelope-type of Somali-land — the " Dibatag " or Clarke's 

 Gazelle [Ammodovcas clavkei). The first noticeable peculiarity of this 

 form is that, unlike all its relatives of the gazelline subdivision, it 

 has its horns curved and projected straight forwards, like those of the 

 Reed-bucks {Cervicapva). So striking is this conformation, that when 

 Mr. Oldfield Thomas received the first pair of horns of this species 

 from his correspondent, Mr. T. W. H, Clarke, he called it Cervicapva 

 clavkeiJ About the same time, however, Captain Swayne kindly 

 forwarded to me two pairs of horns with face-skins attached to them. 

 The examination of these at once showed that Ammodorcas, as Mr. 

 Thomas subsequently proposed to call it, had nothing to do with the 

 Reed-bucks, and was most nearly allied to the Gazelles. Avimodoycas, 

 in fact, as Mr, Thomas ^ has stated, combines the horns of a Reed- 

 buck with the essential characters of a Gazelle, and shows a special 

 relationship to Lithocvanius in the form of the skull, which is unusually 

 long in the occipital region, and has a remarkably small and slender 

 lower jaw. Like Lithocvanms, also, Ammodorcas has an extraordinarily 

 long neck, and the female is hornless. 



Clarke's Antelope is very local in Somali-land, and is not found 

 at all in the neighbourhood of Berbera. Mr. Clarke met with it in 

 the Dolbahanti country, between 46° and 47° east longitude in the 

 interior, where, however, it is said to be common. 



^ Kohl, Ann. Mas. Wien, i., p. 82. 



6 " East Africa and its Big Game," p. 289. 



1 Ann. Mag. Nat. Hist., ser. vi., vol. vii., p. 304. ^ pyoc. Zool. Soc, 1891, p. 207. 



