PREFACE TO THE FIRST EDITION 



This book has grown out of a course in histological technic 

 conducted by the author at the University of Chicago. The course 

 has also been taken by non-resident students through the Extension 

 Division of the University. The Methods were published over a 

 year ago as a series of articles in the Journal of Applied Microscopy, 

 and have called out numerous letters of commendation, criticism, 

 suggestion, and inquiry. The work has been thoroughly revised and 

 enlarged by about one-half. It is hoped that the criticism and 

 suggestion, and also the experience gained by contact with both 

 resident and non-resident students, have made the directions so 

 definite that they may be followed, not only by those who work 

 in a class under the supervision of an instructor, but also by those 

 who must work in their own homes without any such assistance. 



More space has been devoted to the paraffin method than to 

 any other, because it has been proved to be better adapted to the 

 needs of the botanist. The celloidin method, the glycerin method, 

 and freehand sectioning are also described, and their advantages 

 and disadvantages are pointed out. 



The first part of the book deals with the principles of fixing 

 and staining, and the various other processes of microtechnic, 

 while in the later chapters these principles are applied to specific- 

 cases. This occasions some repetition, but the mere presentation 

 of general principles will not enable the beginner to make good 

 mounts. 



The illustrations and notes in the later chapters are not intended 

 to afford a study of general morphology, but they merely indicate 

 to students with a limited knowledge of plant structures the principal 



