viii PREFACE 



natural and interesting. If this be so, it should fasten the reader's 

 attention, and so lead him on from the simple facts of the earlier 

 chapters to those generalisations which are discussed towards the 

 close. 



More than 200 of the illustrations have been specially prepared 

 for this book. My own original drawings are initialled. An almost 

 equal number have been drawn by Dr. J. M. Thompson, and are 

 signed by him. Many beautiful French blocks have been borrowed 

 from Figuier's Vegetable World, and a considerable number are taken,. 

 with the permission of the publishers, from Strasburger's Textbook. 

 By arrangement with the S.P.C.K., many of the excellent drawings 

 of Fungi by the late Professor Marshall Ward, F.R.S., are embodied. 

 They are taken from his Diseases of Plants, a book which has long 

 been out of print. The sources of all these illustrations, and of 

 others not mentioned here by name, are specified in the rubrics, 

 and their use is gratefully acknowledged. 



My sincere thanks are offered to two friends who have carefully 

 read the proofs. Professor W. H. Lang, F.R.S., has given the expert 

 criticism of the Botanist ; while the other, a member of the lay-public,, 

 has made valuable suggestions regarding that clarity of style which 

 is sometimes apt to be forgotten by the technical writer. To both 

 I owe a deep debt of gratitude. 



F. O. BOWER. 



GLASGOW, February 1919. 



