Preface. 



The following pages have been written as a preliminary 

 contribution to a very big and important subject. Various 

 studies in South African plant ecology have been m.ade during 

 the past eight years, and to begin with it was my intention 

 to add another to the series of papers, which I have published 

 ■on this subject, namely, one dealing with the plant succession 

 •in the grasslands of South Africa. A grant towards travelling 

 expenses was made by the Royal Society of South Africa. 

 Various preliminary difficulties had first to be overcome, 

 among which the chief one was the devising of a simpler 

 means of identifying the 500 odd species of grasses, which 

 occur in South Africa. The Key as first drawn up, was not 

 intended to be published, but when I had distributed a few 

 manuscript copies, it was urged by several of those who 

 received them that the key should be included in the publica- 

 tion since it would prove -useful to others. It is hoped that 

 this will be the case, and at any rate it may be of assistance 

 to those who are not in possession of the more elaborate treatise 

 by Dr. Stapf in the Flora Capensis. 



It soon became clear as the work progressed, that many 

 important economic questions were involved, and detailed 

 reference to these added to the length of the paper, so that 

 for various reasons it was thought desirable to publish it in 

 book form rather than in one of the scientific journals, especi- 

 ally since, under the present abnormal conditions, the sending 

 of manuscript overseas leads to very long delays. 



I have to express my indebtedness to Mr. C. G. Smith, 

 of Durban, who has made a generous grant towards the cost 

 of publication. 



To two of my students. Miss M. Batchelor and Miss K. 

 Jameson, my thanks are also due for doing most of the work 

 in connection with the preparation of the illustrations. The 

 map was prepared by Mr. R. Walker. 



