MILNE-EDWARDS, HENRI

(b. Bruges, Belgium, 23 October 1800; d. Paris, France, 29 July 1885)

zoology.

The son of William Edwards, an English planter and militia colonel in Jamaica, and Elisabeth Vaux, Milne-Edwards was born in Bruges, where his parents had retired. (Milne, which he added to his father’s name, was the married name of his godmother and half-sister by a previous marriage of his father.) When Belgium became independent, he chose French citizenship. After medical studies in Paris he acquired a solid background in zoology and in 1832 accepted a post as professor of hygiene and natural history at the École Centrale des Arts et Manufactures. Despite his delicate health, in addition to his teaching he undertook a vast program of research on the invertebrates. His success in this field earned him the Academy of Sciences’ prize in experimental physiology in 1828 and his election to the zoology section of the Academy in 1838. Three years later he was appointed to the chair of entomology of the Museum of Natural History, where he had long had a laboratory. At the time the holder of this chair was responsible for the crustaceans, the myriapods, and the arachnids as well as the insects. Twenty years later the chair of mammalogy became vacant on the death of Isidore Geoffroy Saint-Hilaire, and Milne-Edwards was transferred to it at his own request. In the meantime he had been named professor, and then dean, of the Faculty of Sciences. He was a member of most of the scientific societies of his time and a commander of the Legion of Honor.

In contrast with the tendencies of his contemporaries, Milne-Edwards had been attracted since his youth to the study of the invertebrates, especially those inhabiting the coastal regions. With his friends from the Museum and later with his students, he organized scientific excursions along the shores of the English Channel. Not content with collecting and classifying the animals, he insisted on examining them in their habitat and observed their behavior, their movements, their localization according to the level of the tides, and their modes of obtaining food and of reproducing. Milne-Edwards recorded a wealth of observations in which physiological data were joined with data from comparative morphology. This method, essentially that of ecology, appeared to afford a novel approach to the marine invertebrates, although it was inspired by one that Georges Cuvier had applied to other groups. It led Milne-Edwards to brilliant discoveries and started the creation of maritime laboratories in France and abroad.

Milne-Edwards’ first investigations were primarily concerned with crustaceans. He published a series of memoirs on most of their systems, including circulation, respiration, nerve, and muscle. He began this work with his friend Jean Audouin, who preceded him in the chair of entomology at the Museum, and who accompanied him on his expeditions to the Chausey Isles; he then continued it alone.

These anatomicophysiological investigations served as the basis for the comprehensive three-volume synthesis to which Milne-Edwards dedicated many years—the classic Histoire naturelle des crustacés (1834–1840). In this work he developed some highly original ideas. He reported that the Crustaceae are made up of some twenty homologous metameric segments, the “zoonites,” which are variously fashioned according to the functions they fulfill and the mode of life (free, fixed, or parasitic) of the species. The variety of possible natural combinations, within the limits of a basic framework, is thus virtually infinite. Among Milne-Edwards’ other works are Histoire naturelle des coralliaires (1858–1860), Monographie des polypes des terrains paléozoïques, and the two-volume Recherches pour servir á l’histoire des mammifères (1868–1874).

As an adjunct to his teaching duties at the Faculty of Sciences Milne-Edwards gathered his lectures into a fourteen-volume publication, Leçons sur la physiologie et l’anatomie comparée de l’homme et des animaux, the composition of which was spread over more than twenty years (1857–1881). At the same time he provided a valuable development of his ideas on animal organization in Introduction a la zoologie générale, ou considérations sur les tendances de la nature dans la constitution du règne animal (1858). In this book Milne-Edwards set forth his principal discoveries. These concern the variations that obtain between animal groups, variations which in the final analysis display a great fundamental principle, the law of the division of labor within organisms. Milne-Edwards suspected the existence of this law with his first studies of crustaceans, and he verified it subsequently among the other groups. In the lower animals the same tissue can adapt to different functions. He observed this phenomenon, for example, in the coelenterates, where a single fragment was seen to be capable of regenerating the entire animal. But in animals of higher zoological order, this ability tends to disappear and is progressively replaced by a specialization of the tissues. Systems, or groups of related organs, become individualized in order to carry out precise and exclusive functions: a digestive system, a respiratory system, a reproductive system, and so on.

Within each system each organ has a well-defined role. Therefore the digestive system is divided into a digestive tube and the attached glands; and the digestive tube itself consists of a first region into which food is introduced, a second in which the nutriments undergo the action of the digestive juices, and a third where substances that are useful to the organism are absorbed and where waste products are eliminated. One could reconsider each of these regions and ascertain further subdivisions within them, varying according to diet and other factors. Such specializations, which become more and more precise, determine the rank of an organism in the animal series. It is in large part through the discovery, analysis, and application of these fundamental principles that Milne-Edwards was for years the leader of the French naturalists and that his work remained famous long after his death.

BIBLIOGRAPHY

I. Orginal Works. In addition to those described above, Milne-Edwards’ works include Manuel de matière médicale (Paris, 1825), written with Vavasseur; Manuel d’anatomie chirurgicale (Paris, 1826); Anatomie des crustacés (Paris, 1832); Recherches pour servir à l’histoire naturelle du littoral de la France (Paris, 1832); éléments de zoologie (Paris, 1834); Discours sur les progrès des sciences dans les départements (Paris, 1861); and Rapport sur les progrès récents des sciences zoologiques en France (Paris, 1867).

II. Secondary Literaturte. See M. Berthelot, Notice historique sur Henri Milne-Edwards, membre de l’Académie des sciences (Paris, 1891); Médaille d’honneur offerte à M. H. Milne Edwards. Allocutions de MM. de Quatrefages, Blanchard et J. B. Dumas (Paris, 1881); and G. Pennetier, Discours sur l’éevolution des eonnaissances en histoire naturelle, IV, XVIII^e-XIX^e siècles—zoologie (Rouen, 1920), 497–501.

Jean Antohony