A. Tail quite short. No Gazelline face-markings. Females without horns. _a._ Horns strongly curved backwards. Skull 7 in. or less in basal length. _a^1._ Horns not hooked at tip. (Tibet.) 82. _G. picticaudata._ _b^1._ Horns hooked at tip. (Mongolia.) 83. _G. przewalskii._ _b._ Horns but little curved backwards, not hooked at tip. Skull about 9 in. in basal length. (N. China.) 84. _G. gutturosa._ B. Tail of average length, its terminal half generally more or less crested with black. Face-markings present. Females (except in _G. subgutturosa_) with horns. _a._ Upper part of face white (at least in old age), interrupting the central facial band. _a^1._ No horns in female: size larger. (Central and Western Asia.) 85. _G. subgutturosa._ _b^1._ Horns present in female: size smaller. (Arabia.) 86. _G. marica._ _b._ Central dark facial band uninterrupted by white above. Horns present in the female. _a^1._ Dark colour of back not invaded by white of rump. _a^2._ Dark lateral band indistinctly marked, not strong and blackish. _a^3._ Tip of horns slightly curved inwards or upwards, not bent in to a right angle. _a^4._ Horns of medium length. _a^5._ Horns truly lyrate, the middle portion twisted outwards, the tips reapproaching each other. (Algeria, Egypt, Palestine.) 87. _G. dorcas._ _b^5._ Horns not truly lyrate, more or less evenly diverging upwards. _a^6._ Top of muzzle ordinarily with a black spot on it. _a^7._ Nose simple. _a^8._ Larger: hair rough. (Algeria.) 88. _G. cuvieri._ _b^8._ Smaller: hair smooth: darker. (Arabia.) 89. _G. arabica._ _c^8._ Smaller: hair smooth: lighter. (India and S. Persia.) 90. _G. bennetti._ _b^7._ Nose with a flabby corrugated elevation on it. (Somaliland.) 91. _G. spekei._ _b^6._ Top of muzzle without a black spot. (Somaliland.) 92. _G. pelzelni._ _b^4._ Horns long and very slender. Colours very pale. (Algeria and Egypt.) 93. _G. leptoceros._