DUIKERS AND SMALL ANTELOPES 547 



The skull exhibits a large anteorbital fossa which usually 

 equals or exceeds the orbit in diameter, being smaller than 

 the orbit only in the steinbok, Raphicerus. The bones of 

 the snout are normal in development and arrangement, the 

 premaxillary bones being in contact with the nasals and a 

 lachrymal-nasal sinus being present. The genera included are 

 Nesotragus^ Ourebia, Nototragus, Raphicerus, and NeotraguSy 

 the last named confined to the forested area of the Congo 

 and the West Coast of Africa. 



Key to the Genera 



Anteorbital fossa large, the diameter about equalling that of the orbit; 

 horns heavily ringed at least at the base 

 Size diminutive, about equalling a hare; general coloration red- 

 dish; horns small, projecting straight backward in line 

 with the snout; lateral hoofs absent; no knee-brushes 



Nesotragus 



Size larger, in height equalling a goat; general coloration yellow- 

 ish; horns small, projecting upward at an obtuse 

 angle with the snout; lateral hoofs present; knee- 

 brushes well developed; a bare spot on the side of the 

 head below the ear Ourebia 



Anteorbital fossa small, the diameter only one-third that of the orbit; „ - \j-if%' 

 horns smooth, not ringed Raphicerus /'' "" 



The subfamily N eotragince of Sclater and Thomas is a 

 heterogeneous association of genera of small antelopes. It 

 has been used almost universally by systematic naturalists 

 as a left-over repository for the smaller species of antelopes 

 which are not obviously allied to the better-marked divisions 

 into which the larger may be arranged. It has thus come 

 to be an association based almost solely upon small size. 

 As constituted by its authors in 1892 it included the genera 

 Neotragus, Nesotragus, Ourebia, Raphicerus, Oreotragus, and 

 Madoqua. Gray, some years earlier, in 1872, proposed the 

 family Nesotragidce for Nesotragus, Nanotragus {Neotragus), 



vr 



