36 DE # 14A - CHAPTER I. VARIATION UNDER DOMESTICATION. - Causes of Variability-Effects of Habit and the use or disuse of 7 7 - CHAPTER II. VARIATION UNDER NATURE. - Variability Individual differences Doubtful species - Wide CHAPTER III. STRUGGLE FOR EXISTENCE. Its bearing on natural selection-The term used in a wide sense- Page 75 CHAPTER IV. NATURAL SELECTION; OR THE SURVIVAL OF THE FITTEST. 97 CHAPTER V. LAWS OF VARIATION. Effects of changed conditions-Use and disuse, combined with tion-Correlated variation-Compensation and economy of CHAPTER VI. DIFFICULTIES OF THE THEORY. Difficulties of the theory of descent with modification-Absence or CHAPTER VII. MISCELLANEOUS OBJECTIONS TO THE THEORY OF NATURAL Longevity-Modifications not necessarily simultaneous-Modifica- 262 CHAPTER VIII. INSTINCT. Instincts comparable with habits, but different in their origin- Page 319 INSTRUCTION TO BINDER. The Diagram to front page 140, Vol. i., and to face the latter part of the Volume. ADDITIONS AND CORRECTIONS TO THE SIXTH EDITION. NUMEROUS small corrections have been made in the last and present editions on various subjects, according as the evidence has become somewhat stronger or weaker. The more important corrections and some additions in the present volume are tabulated on the following page, for the convenience of those interested in the subject, and who possess the fifth edition. The second edition was little more than a reprint of the first. The third edition was largely corrected and added to, and the fourth and fifth still more largely. As copies of the present work will be sent abroad, it may be of use if I specify the state of the foreign editions. The third French and second German editions were from the third English, with some few of the additions given in the fourth edition. A new fourth French edition has been translated by Colonel Moulinié; of which the first half is from the fifth English, and the latter half from the present edition. A third German edition, under the superintendence of Professor Victor Carus, was from the fourth English edition; a fifth is now preparing by the same author from the present volume. The second American edition was from the English second, with a |