To Professor Edmond Perrier I am indebted for a copy of his valuable _Lamarck et le Transformisme Actuel_, reprinted from the noble volume commemorative of the centennial of the foundation of the Muséum d'Histoire Naturelle, which has proved of much use. Other sources from which biographical details have been taken are Cuvier's _éloge_, and the notice of Lamarck, with a list of many of his writings, in the _Revue biographique de la Société malacologique de France_, 1886. This notice, which is illustrated by three portraits of Lamarck, one of which has been reproduced, I was informed by M. Paul Kleinsieck was prepared by the late J. R. Bourguignat, the eminent malacologist and anthropologist. The notices by Professor Mathias Duval and by L. A. Bourguin have been of essential service. As regards the account of Lamarck's speculative and theoretical views, I have, so far as possible, preferred, by abstracts and translations, to let him tell his own story, rather than to comment at much length myself on points about which the ablest thinkers and students differ so much. It is hoped that Lamarck's writings referring to the evolution theory may, at no distant date, be reprinted in the original, as they are not bulky and could be comprised in a single volume. This life is offered with much diffidence, though the pleasure of collecting the materials and of putting them together has been very great. BROWN UNIVERSITY, PROVIDENCE, R. I., _October, 1901._ CONTENTS CHAPTER PAGE I. BIRTH, FAMILY, YOUTH, AND MILITARY CAREER 1 II. STUDENT LIFE AND BOTANICAL CAREER 15 III. LAMARCK'S SHARE IN THE REORGANIZATION OF THE JARDIN DES PLANTES AND MUSEUM OF NATURAL HISTORY 23 IV. PROFESSOR OF INVERTEBRATE ZOÖLOGY AT THE MUSEUM 32 V. LAST DAYS AND DEATH 51 VI. POSITION IN THE HISTORY OF SCIENCE; OPINIONS OF HIS CONTEMPORARIES AND SOME LATER BIOLOGISTS 64 VII. LAMARCK'S WORK IN METEOROLOGY AND PHYSICAL SCIENCE 79 VIII. LAMARCK'S WORK IN GEOLOGY 89 IX. LAMARCK THE FOUNDER OF INVERTEBRATE PALÆONTOLOGY 124 X. LAMARCK'S OPINIONS ON GENERAL PHYSIOLOGY AND BIOLOGY 156 XI. LAMARCK AS A BOTANIST 173 XII. LAMARCK THE ZOÖLOGIST 180 XIII. THE EVOLUTIONARY VIEWS OF BUFFON AND OF GEOFFROY ST. HILAIRE 198 XIV. THE VIEWS OF ERASMUS DARWIN 216