PREFACE TO THE FOURTH EDITION 



It is gratifying to the author that the appreciation accorded to 

 Methods in Plant Histology, when it first appeared as a series of articles 

 in the Journal of Applied Microscopy, has continued through three 

 editions of the book. While the chapter headings and general arrange- 

 ment remain about the same as before, the book has been almost en- 

 tirely rewritten. 



Directions for collecting material have been amplified and the 

 preparation of the most familiar laboratory types has received par- 

 ticular attention. While no radical changes have been made in the 

 paraffin method, the process has been shortened and improved; the 

 Venetian turpentine method, introduced in the second edition and im- 

 proved in the third, has come into such general use that the experi- 

 ence of many laboratories has been added to that of our own, and the 

 directions have become so definite that there is little excuse for fail- 

 ures. The cellulose acetate method, which may do as much for woody 

 structures as the Venetian turpentine method has done for its class of 

 mounts, is outlined in a tentative way, and the chapter on 'Thoto- 

 micrographs and Lantern Slides" has been extended and improved. 



The introduction of American stains, which are becoming very ac- 

 curately standardized, has occasioned some modifications throughout. 



The author is even more deeply indebted than before to his col- 

 league, Dr. W. J. G. Land, for suggestions and improvements covering 

 the whole field of microtechnique and photography. He is also indebted 

 to Dr. S. Yamanouchi for improvements applicable to algae and mi- 

 totic figures. Dr. Paul J. Sedgwick is responsible for much of the im- 

 provement in photomicrography and for many of the photomicro- 

 graphic illustrations. To Miss Ethel Thomas, who assisted me for 

 many years, I am indebted for improvements, criticisms, and sugges- 

 tions covering the whole range of the book. Besides, I must thank a 

 host of colleagues and students all over the world for help in all phases 

 of the subject. 



Corrections and suggestions will be heartily appreciated. 



p Charles J. Chamberlain 



October, 1924 



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