viii Preface 



close co-operation secured by the existence of sucli an 

 organisation. Since it was clearly out of the question 

 for a committee as a whole actually to write a book, it 

 was necessary for someone to undertake the task of 

 correlating the contributions of various authors and 

 securing uniformity of treatment. The editor undertook 

 this task on the understanding that he should be allowed 

 a free hand in editing the work of the authors, and this 

 was in nearly every case most willingly accorded. The 

 result of this loyal co-operation has been, it is hoped, to 

 secure a consistent treatment of the whole subject. It is 

 not to be expected that all the members of a large 

 committee should agree in every detail, and each author 

 is of course responsible only for his own contributions. 

 The parts of the book to which authors' names are not 

 attached have been wi'itten by the editor. 



To the following gentlemen, not members of the com- 

 mittee, who have most kindly contributed sections or 

 helped in other ways, the editor expresses his cordial 

 thanks : to Professor Grrenville Cole, F.R.S., of the Boyal 

 College of Science, Dublin, who contributed the section 

 on the Soils of Ireland; to Professor Gr. S. West, of the 

 University of Birmingham, who contributed the section on 

 the British Freshwater Phyto-plankton ; to Dr Home, 

 F.R.S., and Mr Crampton (the latter a member of the 

 committee), of the Scottish Geological Survey, who re^-ised 

 the section on the Soils of Scotland; to Dr J. E. Marr 

 F.R.S. , of the University of Cambridge, who read the 

 proofs of the section on the Soils of England and Wales 

 and contributed a paragraph on the Bast Anglian Heaths 

 as representing a survival of steppe-conditions; to Dr 

 Reginald Scully, of Dublin, who contributed the informa- 

 tion on the vegetation of the Killarney woods; and to 

 Mr J. A. Wheldon, of Liverpool, who kindly contributed 



