VAUCHER, JEAN PIERRE ÉTIENNE

(b. Geneva, Switzerland, 27 April 1763; d. Geneva, 5 January 1841)

botany.

Vaucher was the son of a carpenter, and he expected to follow that trade; but by the age of twelve he knew that he wanted an academic career. He entered college, where he found a general education, including theology and physical sciences, but not botany, which he bagan to study as a leisure pursuit following interest aroused by his exploration of the mountains around Geneva. He was ordained in 1787 and worked as a parish priest from 1797 to 1822, carrying out his duties conscientiously, but always giving much time and energy to botany, which increasingly fascinated him.

A founder member of the Société de Physique et d’Histoire Naturelle de Genève, he was asked in 1794 to give a course of lectures on botany for the Society. These were attended by A. P. de Candolle who became a close friend. By 1798 Vaucher was sufficiently recognized as a botanist and an exceptionally good teacher to be appointed honorary professor of botany in the university, and he held this post until 1807 when he transferred to the chair of ecclesiastical history, which he held until 1839, undertaking additional responsibilities as rector from 1818 to 1821. He married and had children.

Vaucher’s most important work was his observation and interpretation of conjugation and spore formation in algae, particularly in Ectosperma, later renamed Vaucheria by de Candolle. Although the cell theory had not yet been developed, he drew and described the cells showing that they were bounded by separate walls and had a certain degree of independence. He showed how conjugation can occur between cells of threads lying side by side, or cells of a single thread folded over on itself, by means of the communication channel through which the contents of one cell pass to fuse with the contents of the other cell. He also showed male organs, or anthers, protruding to meet other cells and was sure that this was a sexual act, comparable to that found in higher plants and to the copulation of animals. His optical equipment did not allow him to see the actual fertilization, but he correctly inferred it. The newly formed grains, or spores, dropped to the bottom of the ditches in which the algae were found, and in order to verify that they would germinate to give new filaments of Ectosperma in the spring he had to culture them in the laboratory, an uncommon practice at that time. He showed similar conjugation in other primitive algae, and the formation of new nets in old cells of Hydrodictyon.

Other work published by Vaucher was wideranging. Perhaps the most comprehensive was the Histoire physiologique des plantes d’Europe (1804–1841), mainly a taxonomic compilation arranged by the system of Candolle. He wrote monographs on Equisetum (1822) and broomrape (1827) and a paper on leaf fall (1826) that was the first to examine in detail the structure of the base of the petiole.

As a member of the agriculture section of the Société des Arts de Genève from 1796, he carried out some useful investigations on diseases of vines and of wheat, the effects of temperature on plant growth, culture of the potato, and management of woodlands.

BIBLIOGRAPHY

I. Original Works. The descriptions of conjugation and germination in filamentous algae were published as “Sur les graines des conferves,” in Journal de physique, 52 (1801), 344–358, and more fully in Histoire des conferves d’eau douce . . . des Tremelles et des Ulves (Geneva, 1803). Histoire physiologique des plantes d’Europe, t.l. (Geneva, 1804), was reissued in 1830 and the complete work was published in 4 vols. in Paris a few days before Vaucher’s death in 1841. Monographie des Prêles (Geneva–Paris, 1822) was followed by Monographie des Orobranches (Geneva–Paris, 1827). The “Mémoire sur la chute des feuilles” was published in Mémoires de la Société de physique et d’histoire naturelle de Genève, 1 (1821), 120–136, and a report of the work, followed by discussion, appeared in Edinburgh Journal of Science, 5 (1826), 330–338.

Vaucher’s sermons were printed as Souvenir d’un pasteur genevois (Geneva, 1842).

II. Secondary Literature. The most comprehensive biography of Vaucher is an anonymous obituary in Verhandlungen der Schweizerischen Naturforschenden Gesellschaft bei ihrer Versammlung zu Zürich, 26 (1841), 308–313. There is another anonymous obituary in Mémoires de la Société de physique et d’histoire naturelle de Genève, 10 (1843), xxiv–xxvi, and one by A. de Candolle in Annals and Magazine of Natural History, 10 (1842), 161–168, 241–248, translated from the Bibliographie universelle de Genève (1841). The Souvenir has a 22–page biographical preface by Vaucher’s son.

Two modern evaluations of his work are by C. Baehni, “II y a 150 ans, le Genevois, J. P. Vaucher découvrait la fécondation chez les algues” in Les Musées de Genève, 10 no. 10 (1953), and by G. de Morsier, “Contribution à l’histoire de la genétique,” in Physis, 7 (1965), 497–500.

His relations with the university may be found in C. Borgeaud, Histoire de l’Université de Genève, II (Geneva, 1909); and Candolle’s tributes are in his Histoire de la botanique Genevois (Geneva, 1830), which includes a bibliography of 14 items, and in his Mémoires et souvenirs de Genève (Geneva, 1862).

Vaucher’s publications can be traced through the Royal Society Catalogue, which lists 15 items, and G. A. Pritzel, Thesaurus literaturae botanicae (Leipzig, 1872), entries 9704–9710.

Diana M. Simpkins