An Outline of 
the Theory of Organic Evolution 
With a Description of some of 
the Phenomena which it explains 
By MAYNARD M. METCALF, Ph.D. 
Professor of Zodlogy, Oberlin College, Oberlin, Ohio 
THIRD EDITION, FUNDAMENTALLY REVISED 
Cloth, 8vo, Colored Plates, $2.50 net 
The lectures out of which this book has grown were written for the 
author’s students at the Woman’s College of Baltimore, and for others in 
the college not familiar with biology who had expressed a desire to attend 
such a course of lectures. The book is, therefore, not intended for biolo- 
gists, but rather for those who would like a brief introductory outline of 
this important phase of biological theory. 
It has been the author’s endeavor to avoid technicality so far as possible, 
and present the subject in a way that will be intelligible to those unfamiliar 
with biological phenomena. The subject, however, is somewhat intricate, 
and cannot be presented in so simple a manner as to require no thought 
on the reader’s part; but it is hoped that the interest of the subject will 
make the few hours spent in the perusal of this book a pleasure rather 
than a burden. 
In many instances matter that might have been elaborated in the text 
has been treated in the pictures, which, with their appended explanations, 
form an essential part of the presentation of the subject. This method of 
treatment has been chosen both for the sake of the greater vividness thus 
secured and because it enables the book to be reduced to the limits de- 
sired. Many of the illustrations have been obtained from books with 
which the reader may wish later to become familiar. 
THE MACMILLAN COMPANY 
Publishers 64-66 Fifth Avenue New York 
