GEN A I OR ISABELLE GAZELLE 255 



straightness of the horns, of which the record length is 15! inches. 

 In height the bucks stand about 28 inches at the shoulder, or slightly 

 more than the edmi. The colour of the upper-parts is unusually light 

 (a feature indicated by the Arabic name ghazal abiad, i.e. white 

 gazelle), and may be described as pale sandy fawn, with the distinctive 

 gazelle-markings very faintly indicated. On the face, for instance, the 

 dark streaks are sandy instead of rufous, while the light band on the 

 flank is almost imperceptible, and the dark one below pale sandy with 

 the merest suspicion of a brown tinge. The tail is sandy at the base, 

 and gradually darkens to brownish black towards the tip ; and the 

 ears are nearly white. 



Compared with the rich-coloured dorcas, the rhim has been appro- 

 priately described as a washed-out species. 



The sandy plains of the interior of Algeria, Tunisia, and western 

 Egypt, and thence southwards into Nubia and Sennar, form the 

 habitat of the rhim, whose mode of life is doubtless similar to that 

 of gazelles in general. 



The name of Gazella leptoceros abu-Jiarali, Heuglin, is available for 

 the rhim of the Libyan desert in the neighbourhood of Lake Natron, 

 if it prove to be distinct from the typical representative of the species. 



THE GENAI OR ISABELLE GAZELLE 



(Gazella i sab el la) 

 Genai, TRIBES OF RED SEA LITTORAL 



Like the King's cream-coloured state horses, this gazelle takes its 

 name of isabellc from its colour, which is of the normal gazclline type. 

 From all the foregoing species the isabelle gazelle is readily dis- 

 tinguished by the sharp inward bending of the tips of the horns, which 

 form decided hooks, with their main axis almost at right angles to 

 that of the basal portion. In this respect it is practically a miniature 

 of Sommerring's gazelle. The shoulder-height is about the same as 

 in Pelzeln's gazelle, that is to say about 25 inches; while the 

 maximum recorded horn-length is only io| inches. The colour of 

 the whole of the upper-parts is very pale fawn or sandy ; the dark 

 flank-band, as well as the face-markings, being merely a somewhat 

 deeper shade of fawn. 



This paleness of tone distinguishes the species from its near ally 



