LAMARCK, JEAN-BAPTISTE PIERRE ANTOINE DE MONNET, Chevalier de, the celebrated French naturalist, was born of a noble family, at Bazentin, in Picardy, in 1744. Destined by his father for the church, he received the elements of his education in the Jesuits' College at Amiens, where he was distinguished by his abilities and ardent thirst for knowledge; but at the early age of seventeen he relinquished all thoughts of an ecclesiastical career, entered the army, and was attached to the division of the Duc de Broglie, during his contest with Prince Ferdinand of Brunswick, in Westphalia. The young Lamarck exhibited great courage, and received a severe wound in battle; but, on account of impaired health, he was soon compelled to retire from the service.
He then commenced the study of medicine at Paris; but the bent of his mind was to the physical sciences, and he made considerable proficiency in natural philosophy and botany. His first publication was entitled Recherches sur les Causes des Principaux Faits Physiques, in which he propounded theories of heat and electricity, which were more fully developed in his subsequent publication, Mémoires de Physique et de l'Histoire Naturelle, but which would have been forgotten had it not contained the germ of his speculations on animal life. In 1778 he sent to the Académie des Sciences some ingenious observations On the Formation of Clouds; and in the same year he was appointed, through the friendship of Buffon, assistant to Daubenton, in the Cabinet du Jardin du Roi, and was sent, with the son of his patron, into Germany and Holland, to collect rare specimens of plants for the royal collection. More fortunate than his companion, Lamarck survived the horrors of the Revolution, in which the young Buffon fell a victim to the butcheries of Robespierre.
In 1780 Lamarck produced his Flore Française, and
undertook to furnish the article Botanique for the Encyclopédie Méthodique. The first volume of that article appeared in 1783, and a second in 1786; but the Revolution put a stop to his progress in the work, which reached no farther than 600 in the alphabetic arrangement.
It does not appear when he first directed his attention to zoology, but he must have made considerable progress in that science before the Revolution, for in 1793 he was appointed one of the conservators of the superb museum of natural history at Paris, and the care of the invertebrate animals was confided to him. In 1794 he began to give lectures on that branch of zoology, and continued to do so until 1818, when age, and the failure of his sight, rendered him incapable of that duty, and he resigned his office to Lacroix, Cuvier's assistant in the entomological department of the Régne Animal.
The first result of Lamarck's researches in his department of the museum appeared in a volume termed Système des Animaux sans Vertèbres, published in 1801, which may be considered as the forerunner of his great work on this subject, one of the most valuable treatises which has ever appeared on this difficult branch of natural history.
In 1809 he produced his Philosophie Zoologique, in two volumes, containing much that is exceedingly valuable; but we here find stated fully the extravagant hypothesis, broached in his Recherches, of the progressive development of animal functions, and the production of new organs, by the exertion of the will of the individual. This opinion is best given in his own words: "La production d'un nouvel organe dans un corps animal, résulte d'un nouveau besoin survenu, qui continue de se faire sentir, et d'un nouveau mouvement que ce besoin fait naître et entretenir." "Tout ce qui a été acquis, tracé ou changé, dans l'organisation des individus pendant le cours de leur vie, est conservé par la génération, et transmis aux nouveaux individus qui proviennent de ceux qui ont éprouvé ces changements."
The example which he adduces to support this strange doctrine is that of a molluscous gastropod. A snail, for instance, as it draws itself along, he imagines to feel the want of organs for examining the bodies it encounters, and therefore makes efforts with some of its anterior parts to touch those opposing bodies, by which exertion of its will, constantly operating, portions of nervous and other animal fluids must be determined towards its head; such reiterated efforts will in time, he says, cause two or more tentacula to spring from its head; "and this, without doubt, has happened to all races of gastropods, in which necessity has induced the habit of touching bodies with some part of their head!" Were this view to be received as the cause of changes in animal organization, the different species and genera, and even classes of animals, would long ago have been undistinguishable by diversity of organs; and the same laws, applied to the higher animals, would lead to the belief that terrestrial creatures may have derived their origin from the desire of aquatic animals to enjoy atmospheric existence; and even man himself might have passed, by long-continued appetite, from the form of a fish, or may hereafter obtain the wings of a bird!
The work on which the fame of Lamarck justly rests is his admirable Histoire Naturelle des Animaux sans Vertèbres, which successively appeared, in seven volumes 8vo, between the years 1815 and 1822. In this work he has founded his classification more on differences in anatomical structure than any of his predecessors in the same branches of zoology, and has therefore succeeded in a more perfect distribution of invertebrate animals. He divides the whole animal kingdom into three primary groups, which he denominates the Apathetic, the Sensible, the Intelligent. In the first he includes the classes—1. Infusoria, 2. Polyparia, 3. Radiaria, 4. Vermes; in the second, 5. Insecta, 6. Arachnida, 7. Crustacea, 8. Annelida, 9. Cirripeda, 10. Mol-