vi PREFACE 



climax. Adjective nomenclatures so extensively developed in fields 

 of limnology and oceanography are deplored by the writers as admit- 

 ting of an almost unlimited degree of vagueness without commitment 

 to status for either the community or its habitat. On the other hand, 

 the letter nomenclatures used by European students of the sea prove 

 to be very difficult because many of the generic names which have 

 'been abbreviated are not known to the reader. 



The general plan of the book is in the main that of the senior 

 author. It was already on hand when collaboration began and has 

 been modified only through rearrangement of chapters and the omis- 

 sion of treatments of several large biotic communities such as decidu- 

 ous forest, coniferous forest, and desert. Their omission results from 

 lack of detailed knowledge of the animal relations, and hence it 

 has become desirable to restrict such discussion to the grassland 

 biotic community. In preparing the book, the authors have not sepa- 

 rated their work by making a sharp division into the fields of botany 

 and zoology. The plant ecologist has had experience in the field 

 of animal ecology, and vice versa, so that separation along these 

 lines was not easy. For example, the organization of most of the 

 material in Chapters 1 and 2 w'as made by the senior author, who also 

 undertook to prepare the tables dealing with the food of birds and 

 the material on bird migration, on all matters relative to sunspots, and 

 the general index. The junior author is almost entirely responsible 

 for the chapters on communities of water; he played a large part in 

 the organization of the grassland chaptef and the chapters on climax 

 and sere, and in the preparation of the illustrations. He did the 

 greater part of the work on the bibliography and prepared the author 

 index in connection with it. After the book was considered prac- 

 tically complete, the authors had the good fortune to have the manu- 

 script read and criticized by their sympathetic colleague, Professor 

 John Phillips of South Africa, who made many valuable suggestions 

 and caused them to delay publication in order to give the manuscript 

 an additional period of study. 



In the scientific nomenclature for American plants and for both 

 European plants and animals, the authors' names are omitted. Au- 

 thors' names for all American animals are included at least once, 

 usually at the point of most important discussion of the species, except 

 in a few cases where all the names come from a single source cited in 

 the paragraph or section where they occur. 



Santa Barbara, California Champaign, Illinois 



November 1038 November 1938 



