PREFACE vii 



of considerable use, and the Principal (Sir Oliver Lodge) most 

 kindly obtained for me a grant towards the cost of preparing 

 the illustrations. By the courtesy of Dr A. B. Rendle, Keeper 

 of the Botanical Department of the British Museum, and that 

 of the Director of Kew Gardens, the Herbaria at those insti- 

 tutions have been consulted and much useful information lias 

 been derived therefrom. Thanks are also due, and are hereby 

 gratefully tendered, to Herr H. Sydow (of Berlin) and Mr J. 

 Ramsbottom (of the British Museum) who have both given 

 unstinted help, to Mr T. B. Roe (a very successful collector 

 of specimens), Professor A. H. R. Buller, Mr A. D. Cotton 

 Mr H. J. Wheldon, Mr C. Crossland, Mr J. Adams, Sir Frederick 

 Moore, and many others in a smaller degree. 



W. B. GROVE. 



The Botanical Laboratory, 

 University op Birmingham. 

 July, 1913. 



