xii PREFACE TO THE ENGLISH EDITION 



Among the Ascomycetes and the Uredineae are numerous 

 questions already framed for investigation, and I know of no 

 department of botanical study more fascinating than the scien- 

 tific hunting for the hetercecious forms of ^Ecidiomycetes : the 

 work combines all the excitement of a true hunt with the 

 intense intellectual pleasure implied in the demand for the 

 severest critical observation, and skilful and delicate manipula- 

 tion of the microscopic cultures. 



Again, the whole question of wound-rot, opened up on 

 pp. 236-237, is one which demands long and thorough inves- 

 tigation ; not only to clear up the many chemical problems 

 involved, but also to explain the exact behaviour of sapro- 

 phytic fungi and bacteria, and the part they play in the 

 phenomena. 



My duties as Editor of this work have not seemed to be 

 such as to demand that I should express my own opinions on 

 the subjects raised, and I have almost confined myself to merely 

 noting the occurrence of the principal diseases in this country 

 (since the original is written for German readers), and to adding 

 a few explanatory sentences wherever it has seemed useful in the 

 interests of the lay reader to do so. In some respects Hartig's 

 book is a popular one by which I mean it appeals to a wide 

 circle of readers not professionally engaged in the study of 

 this branch of science and it has seemed advisable, therefore, 

 occasionally to interpolate a short note in explanation of some 

 of the more technical terms employed. Short notes are apt 

 to be insufficient in such cases ; but it would so obviously have 

 been out of place to overload the author's work with long 

 disquisitions on the matters referred to, that I have been 

 constrained to risk their being occasionally too brief. 



Here and there I have ventured, however, to go a step 

 further, and add a reference which may be useful, and this in 

 face of my full recognition of the fact that Hartig's book is 

 an exposition of his own view of his own work rather than 

 that of others. 



In all cases I have been careful to place my remarks, more- 



