252 Transactions South African Philosophical Society, [vol. xii. 



head produced into a carina emitting on each side a long, compressed, 

 recumbent, sHghtly arcuate horn, reaching beyond the base of the 

 prothorax, and shghtly truncate at tip, in the middle of the carina 

 there is on each side near the base of the long horn a very much 

 shorter one also curving slightly backward, and occasionally spinose 

 at a short distance from the apex ; the prothorax is broadly and deeply 

 excavate in the anterior part, and on each side of the excavation 

 there is a sharp, compressed, long, slightly curved tooth ; apical spur 

 of anterior tibiae thick and curving slightly outwards. In the small 

 development the cephalic horns are as in 0. varus (fig. 10a), but the 

 median part of the carina is alone dentate, the prothoracic cavity is 

 reduced to a mere depression, and the two compressed teeth to two 

 short, blunt tubercles set close to one another. 



Female : Clypeus sub-triangular and produced in the centre into 

 a slightly recurved, short triangular tooth, frontal carina very dis- 

 tinct, sub-basal one with a moderately long, sub-conical tubercle at 

 middle ; prothorax very slightly excavate at middle, and having two 

 small tubercles in the centre of the anterior, declivous part ; tip of 

 apical spur of anterior tibiae bent inwardly at right angles. 



Length 18-21 mm. ; width 11-13 mm. 



0. furcifcr is the small development, and the description of 0. 

 plato was made from a fully developed male. 



Hab. Damaraland, Southern Ehodesia (Victoria Falls). 



Onthophagus bicallosus, Klug, 



Plate XXXVI., fig. 7 ; Plate XXXVIII., fig. 21. 



Monatsb. Beri. Ac, 1855, p. 653; Peters' Eeis., 1862, p. 232. 



0. mctallicus, Fahr., Insect. Caffrar., ii., p. 265. 



Coppery red, not very shining, turning at times to green ; genae 

 rounded, clypeus semicircular, head deeply and closely punctured, 

 briefly pubescent ; prothorax ampliate laterally, convex, marginate 

 in front and on the sides but not along the base the median part of 

 which is sharply aculeate, it is covered with very closely set, 

 elongate granules, and the median part has in both sexes a very 

 broad, median, longitudinal furrow edged on each side by a smooth, 

 round carina, at the apex there is also a minute median, smooth 

 raised line in the centre of the median sulcus ; elytra ampliato-ovate, 

 finally striate, the striae are not geminate, the intervals are very 

 briefly pubescent and covered with extremely closely set, elongated 

 granules, the second interval is nearly twice as broad as the third, 

 and has a rudimentary median stria, the suture and the third and 



