Pits are present in the forehead of the skull, and the horns are ringed for part of their length, with a compressed base; their form being often lyrate,.
The horns are more or less lyrate,and generally developed in both sexes; there are frequently brushes of hair on the knees.
With the palla, or impala(A epyceros melampus), we reach an exclusively African genus, characterized by the lyrate horns of the bucks, the absence of lateral hoofs, and the presence of a pair of glands with black tufts of hair on the hind-feet.
The long face, high crest for the horns, which are ringed, lyrate and more or less strongly angulated, and the moderately long tail, are the distinctive features of the hartebeests.
Both sexes carry lyrate horns; the shoulder-height of an adult male is about 30 in., and an average pair of horns measures 14 in.