Synthesis of knowledge and new research on Aristida rhinochloa amphitropical African grass. This paper gives a survey on the phytochorology of Aristida rhiniochloa (vegetal environment, ecological optimum). The geography of this species, the origin of which doubtless is tropical, is sketched. Further on the basis of a cultivation experiment a differentiation of this taxon into a typical variety and two ecological varieties is being suggested. Finally, the results of experimental investigations towards an Evolution are presented.