For the incorporation of various grasses in the herbaria of our institutes, we are constantly looking for the correct names to accept, according to the priority. The study of the existing names, as they are given in the Index Kewensis, is therefore indispensable. Working in various genera of the grasses we find, however, that many names are not tenable, because they were accepted without studying the whole literature of the subject. It appeared that, various names are omitted in the Index Kewensis, and indications given in various papers are sometimes neglected. Thus, the well-known and characteristic Aristida rhiniochloa HOCHST., already described in the year 1855 and treated by me in the Critical Revision (p. 510) and in my Monograph, is not yet given in the Index, although many of my new species are mentioned.