PREFACE. Vll 



viously published descriptions, but have repeatedly and 

 thoroughly examined the various types for myself as 

 indeed I have done for the whole of this book. As a 

 matter of fact, some of these type plants have hitherto 

 been very inadequately and inaccurately described this is 

 especially the case with Pellia and Funaria. In order to 

 help the teacher and the student alike, I have in this 

 section given full directions for the collection and culture 

 of the typical plants dealt with. 



I have made no attempt to illustrate the book completely. 

 Apart from figures representing various pieces of apparatus 

 I have simply given drawings here and there to serve as 

 models of the sort of sketches to be made on a much 

 larger scale, of course in the student's note-book, which 

 should be of good size and consist of drawing-paper with 

 or without interleaved writing-paper. For the photo- 

 graphic illustrations, I am indebted to Messrs. Flatters and 

 Garnett (32 Dover Street, Manchester) ; and for various 

 blocks illustrating apparatus, to Messrs. Flatters and 

 Garnett, to the Cambridge Scientific Instrument Co. (Fig. 

 2), to Messrs. Leitz, to Messrs. Baird and Tatlock (Cross 

 Street, Hatton Garden, London), and to The Bausch and 

 Lomb Optical Company (19 Thavies Inn, Holborn Circus, 

 London). Lecturers and students should write to these 

 firms for catalogues of apparatus and materials. 



In preparing a practical handbook of this scope it is 

 very difficult to avoid errors in detail, and I should esteem 

 it a favour if Lecturers and others who use the book would 

 point out any inaccuracies, or make criticisms regarding the 

 general scope and arrangement of the work. 



F. CAVERS. 



LONDON, Sept. 26th, 1911. 



