74 DR. A. GUNTHER ON ANEW ANTELOPE.  [Feb. 19, 
horns trihedral in shape at the base; and if we imagined the longi- 
tudinal axis of the horns of our specimen twisted outwards, a form 
a. Horns of Antilope triangularis. 
a. Front view. 0. Side view. c. Transverse section of the horn, of 
the natural size, taken at the place marked x. 
of horn would be produced which could not be separated from 
Tragelaphus. And there is no doubt that the ancestral form of 
Tragelaphus must have resembled, or been identical with, our type. 
