PKEFACE. VII 



authors who have advanced the study of petrified plants of the 

 Coal period, one should not forget the valuable services that 

 have been rendered by such men as Butterworth, Binns, Wilde, 

 Earnshaw, Spencer, Nield, Lomax and Hemingway, by whose 

 skill the specimens described by Williainson and others were 

 first obtained and prepared for microscopical examination. 



I am indebted to many friends, both British and Continental, 

 for help of various kinds. I would in the first place express my 

 thanks to Professor T. McKenny Hughes for having originall)' 

 persuaded me to begin the study of recent and fossil plants. 

 I am indebted to Prof Nathorst of Stockholm, Dr Hartz of 

 Copenhagen, Prof. Zeiller, Dr Renault and Prof Munier-Chalmas 

 of Paris, Prof. Bertrand of Lille, Prof Stenzel and the late 

 Prof. Roemer of Breslau, Dr Sterzel of Chemnitz, the late 

 Prof Weiss of Berlin, the late Dr Stur of Vienna, and other 

 continental workers, as well as to Mr Knowlton of Washington, 

 for facilities afforded me in the examination of fossil plant 

 collections. My thanks are due to the members of the Geo- 

 logical and Botanical departments of the British Museum ; 

 also to Mr E. T. Newton of the Geological Survey, and to 

 those in charge of various provincial museums, for their 

 never-failing kindness in offering me every assistance in the 

 investigation of fossil plants under their charge. Prof Marshall 

 Ward has given me the benefit of his criticism on the section 

 dealing with Fungi; and my friend Mr Alfred Harker has 

 rendered me a similar service as regards the chapter on 

 Geological History. I am especially grateful to my colleague, 

 Mr Francis Darwin, for having read through the whole of the 

 proofs of this volume. To Mr Shipley, as Editor, I am under a 

 debt of obligation for suggestions and help in various forms. I 

 would also express my sense of the unfailing courtesy and skill 

 of the staff of the University Press. 



My friend Mr Kidston of Stirling has always generously 

 responded to my requests for the loan of specimens from 

 his private collection. Prof Bayley Balfour of Edinburgh, 



