Purpose of the Book

The purpose of this book is well expressed in the Preface by the statement of the authors that each had a feeling that the problems of the origin of species had not been settled, and alone each one felt unable to attack and settle so momentous a question; but apparently they found strength in union and have attempted to settle the question of species-making.

Introduction

Most naive is their statement in the Introduction: "Our aim in writing this book has been twofold: In the first place, we have attempted to place before the general public in simple language a true statement of the present position of biological science. In the second place, we have endeavored to furnish the scientific men of the day with food for reflection."