PREFACE TO THE FOURTH EDITION 



The fourth edition of this book, like the two preceding ones, 

 has been prepared with the hope that by certain changes and addi- 

 tions, it will meet the still increasing demand for a text-book which 

 shall present the subject of Physiology as well as Anatomy, in a 

 manner both practical and available to the student. 



To include these two large subjects under one cover, with the 

 necessary brevity and still with sufficient clearness, is a task with 

 difficulties of its own, but it is undertaken with the earnest en- 

 deavor to meet the demand created by present requirements as 

 well as may be with the inevitable problem of selection or omission, 

 which, however carefully considered, must remain a matter of 

 judgment and experience. 



The plan has been adopted in the descriptions to emphasize 

 those characteristics which are most essential and which may be 

 most readily grasped and, by reason of practical application, 

 remembered. 



The original purpose of the author to provide a special text- 

 book of Anatomy still remains in effect, since only by means of 

 a knowledge of structure -and form can an understanding of use 

 or function be reached. 



The student is referred to the Glossary for the meaning of 

 unfamiliar terms, and to the lines of smaller type for various par- 

 ticulars which may be found useful as experience indicates the 

 need for reference. 



The original illustrations drawn for this book are all retained 

 and several new ones from other sources are added. 



Again the author desires to express appreciation of suggestions 

 and kind words from officials of schools where the book is in use. 



PHILADELPHIA ELIZABETH R. BUNDY. 



