NOVITATES ZOOLOGICAE XXI. 1914. 157 



of ?«^ is, for instance, in tlie tmck of albonntata 12 min., buf, in the bnck ci^ Irteapfis 

 only 10 mm. 



The t.ypical Ga-dla nififroim iVora West Africa evidently differs from G. r. 

 laevipex in several points, jndj<ing from the Book of Antelopes. The authors of 

 this work write (vol. iii. p. 105) rei];arding the western animal: "The knee-binshes 

 are quite imperceptible in these three specimens [from the West C!oast of Africa], 

 and the knees are perfectly smooth." This is, as already mentioned above, more 

 than can be said about the types of G. r. laempes. Both male and female of the 

 western race are said to have "a slight blackish nose-s|)ot," while laevipes has no 

 trace of such a spot. The cranial measurements communicated in the Book of 

 Antelopes are derived from "a slightly immature male." They are, tlierefore, 

 perhaps hardly suitable for compaiison with those recorded above; however, the 

 greatest breadth of this male skull is said to be 3 in., or in millimeters 76'17, and 

 this nieasnrement is considerably less than the corresponding one, even of the 

 female Zat'tv/ic.s (87) and the female albonotata (83). The distance from " muzzle 

 to orbit" is said to be 3'95 in., or abont lOO mm., and this measurement is also 

 smaller than the corresponding one of the females of albonotata and laeripes. From 

 this we might presume that the typical western Ga~nlla rufifrons is a smaller 

 animal than its eastern relatives. 



Gazella nifina Thomas is said to be larger than ti. rufifrons, but at the same 

 time "closely similar." It differs, however, in having the "light facial streaks 

 not white, but sandy," and the colour throughout more brilliant. The knee-brushes 

 are said to be dull rufous. This Gazelle can thus hardly be mixed up with albonotata 

 or rufifrons, although its cranial length is almost the same as that of the former 

 race {albonotata), or if anything' rather longer. 



Gazella tdonuva Heuglin alsoi belongs to the same group, and apjiears some- 

 times to have been confused with other species. It differs, however, in so many 

 points from the species mentioned that it ought not to be difficnlt to distinguish it. 

 The light facial streak is "scarcely or not perceptible on the sides of the muzzle." 

 The light lateral band of the body is not sharply defined, and there is a buff band 

 between the dark band and the white of the belly, but the pygal band is absent. 

 The horns are also very different, having sharp hooks twisted inwards towards each 

 other. 



It is more difficult to decide what von Lorenz's Gazella salmi is, as he has only 

 di'scribed * a head and some horns. It appears, however, most probable that it 

 is identical with the eastern race of Gazella rufifrons, which Huudevall named 

 laempes. There are hardly any differences between von Lorenz's description of 

 G. salmi and Sundevall's type of laempes, e.xcept that the horns of the latter are 

 a little shorter and have only twelve rings, against thirteen to fifteen recorded for 

 the former. This cannot, however, be regarded as any racial difference. 



In any case Gazella albonotata bears very little relationship to " G. salmi." 

 In fact, I must regard Gazella albonotata as a very close relative, not to G. rufifrons 

 and its subspecies, but to (Jazella t/iomso/ii, or as the nortliernmost representative 

 of the latter, of which it perliaps only is a subspecies. 



The following characteristics, among others, are common to G. albonotata and 

 G. t/iom.ioni, and these distinguish both from G. rufifrons, G. rufina, and G. tilonura : 

 the light facial streak is white, and reaches from the region round the eye to the 

 nostril ; the central facial streak is mixed with black, and produces a black or 



* Sitzlier, d. h. Ahad. d. Wissensch. Wii'ii. Bd. cxv. Heft. 1, p. 21. 



