PREFACE 



The present volume brings together in brief form the 

 fundamental principles of biology for the college student and 

 the general reader. 



It is well recognized that there is no adequate substitute 

 for detailed laboratory work on the structure and physiology 

 of representative organisms as a means of affording a first- 

 hand knowledge of the facts and methods of biology. How- 

 ever, the author has realized with increasing force that the 

 student's correlation of the laboratory data from day to day 

 and accordingly his appreciation of the broader aspects of 

 the subject are greatly enhanced by a synchronous 'running 

 account' of the underlying principles. The material in 

 this volume has proved to be of great value for this purpose 

 in a course on General Biology elected each year by several 

 hundred Yale undergraduates. 



The large problems of life are common to both zoology and 

 botany, and therefore both animals and plants have been 

 drawn upon for illustration and discussion. This method of 

 presentation accords with the author's conviction that the 

 general biological viewpoint is the most favorable means of 

 approach both to a broad knowledge of living phenomena 

 as a part of a 'liberal' education, and to more advanced 

 studies in zoology and botany which are prerequisite for 



