FOREWORD. 



The study of Phytophthora on Ricinus was undertaken at the 

 suggestion of Dr. E. J. Butler, m.b., f.l.s., the Imperial Mycologist. 

 I have to express my gratitude to him for his ever ready help and 

 invaluable advice which I have received from him. I have also to 

 express my thanks to Mr. F. J. F. Shaw, b.sc, a.r.c.s., f.l.s., 

 the Supernumerary Mycologist, for the microphotographs taken 

 by him. 



J. F. D. 



