Candolle, Augustin-Pyramus De

(b. Republic of Geneva, 4 February 1778; d. Geneva, 9 September 1841),

botany, agronomy.

The son of Augustin de Candolle, a magistrate of the Republic of Geneva, and of the former Louise Eléonore Brière, Candolle developed a love for the “science aimable” while still quite young. His family moved from Geneva to Grandson, in the Vaud district, on the shore of the Lake of Neuchâtel. At the age of fourteen Candolle undertook solitary, ambitious botanizing expeditions and in his plant-study notebooks described, with remarkable attention to detail, the flora of the Swiss Plateau and of the Jura.

In 1794 the Candolle family was again in Geneva, and Augustin was attending the Collége de Calvin. He had decided to become a botanist but obeyed his father’s, wish that he first study medicine. For two years Candolle followed the courses at the Academy of Geneva. He was nevertheless able to continue his botanical excursions into the countryside around Geneva and in nearby Savoy, gathering numerous specimens and making observations that were later useful in preparing the monographs that brought him fame.

At about this time Candolle became acquainted with the botanist Jean Pierre Vaucher, pastor of the church of St. Gervais, who later wrote a remarkable work on freshwater algae. Vaucher had great influence on Candolle, with whom he shared his observations on the fertilization of the Confervae; these observations gave rise to Candolle’s classic memoir, Histoire des confervas d’eau douce (1803). Vaucher also showed Candolle part of the manuscript of a work, not published until late in his life, that gave orientation to Candolle’s biological research. This work of Vaucher’s, Histoire physiologique des plantes d’Europe, was indisputably the inspiration for the Prodromus, the first sections of which Candolle published in 1824.

Another acquaintance of Candolle’s was Jean Sénebier, also a pastor who was interested in plant physiology. Through Sénebier, Candolle became aware of the importance of the life processes of plants, and through his contact with this remarkable biologist—whose major contribution was his significant observations on photosynthesis—Candolle was to become not merely a distinguished taxonomist but also a botanist of far wider accomplishment.

A third influential friend in this period was Horace-Bénédict de Saussure, one of the most illustrious Genevan scholars of the eighteenth century. Through Saussure, Candolle was initiated into the study of mathematics, philosophy, and physics; he became interested in geology and fossils and went on to study the flora of the past as well as of the present.

In 1796 Candolle went to Paris to study both the natural sciences and medicine; there, as in Geneva, he sought contact with the greatest scholars in the city. He was a frequent visitor to the Muséum d’Histotre Naturelle and had exciting discussions with Georges Cuvier on the origin of species and on the new science of paleontology. He also became friendly with Lamarck. At this point Candolle decided definitely to abandon the study of medicine for the natural sciences, particularly botany.

In 1797 Candolle began to think seriously of publishing the results of his research. His early memoirs dealt more with experimental biology than with descriptive taxonomy. He made a careful study of the germination of legumes and a detailed report on the absorption of water by seeds under various conditions. He was interested in lichens and tried, by rudimentary means, to analyze their nutrition. He gathered important information on medicinal plants. Finally, in 1798 Candolle decided to publish his first botanical paper; it was on Reticularia rosea, a plant that he had discovered in the Jura. During the years 1799–1802 Candolle brought out his first important work (in twenty sections), Plantarum historia succulentarum, to which he added eight final sections in 1803.

Meanwhile, the political situation in Geneva was growing worse, and Candolle decided to settle in Paris, where he remained until 1808. Besides his botanical work, which he pursued enthusiastically, he occupied himself with the welfare of the poor and published several essays on philanthropy and political economy. In 1808 Candolle was called to Montpellier, to the chair of botany at the École de Médecine and the Faculté des Sciences; he lived there until 1816. The peaceful life of this provincial town allowed him ample opportunity to organize the countless research papers that he had accumulated during his ten years in Paris. Eventually, however, he found such a life monotonous. The Academy of Geneva had made Candolle an honorary professor in 1800; in 1802 the directors had offered him a chair in zoology, which he declined on the ground that his work was more oriented toward botany. In 1816, however, when a chair was established for him in natural history, he left Montpellier for Geneva.

With the support of the Republic and Canton of Geneva (which had become part of Switzerland in 1815), as well as of the people of Geneva, Candolle completely reorganized the botanical gardens created by the Société de Physique in 1791; these gardens opened on 19 November 1817 and served as a model of the genre for many years. Candolle played an active role in the creation of a museum of natural history that, through the support of Henri Boissier, rector of the Academy, had begun as early as 1811 to receive the physics and natural history collections of many Genevan scholars. He was also responsible for the founding of the Conservatoire Botanique. The excellent collections of this center of taxonomic research permitted it to make important contributions to the development of botany in the nineteenth century. During his twenty-five years in Geneva, Candolle was active in many fields besides botany. He was associated with the public library, the Société des Arts, and the Musée des Beaux-Arts. He was concerned with the politics of his canton and from 1816 to 1841 was a member of its representative body. He was rector of the Academy from 1831 to 1832.

When Candolle retired from the Academy in 1835, his chair was divided: his son Alphonse succeeded to the chair of botany and his best student, Jean Francois Pictet, to that of zoology. The six years remaining to Candolle were clouded by illness. His death was greatly mourned by his colleagues and fellow citizens.

The writings of Candolle are considerable and touch on many areas of plant biology. The world’s botanists have shown their admiration of and gratitude to the Genevan naturalist by dedicating more than 300 plants to his memory: one family (Candolleaceae) and two genera (Candollea and Candollina) have been named for him. Candolle signed nearly 180 memoirs and other works, and at his death he left some forty unfinished manuscripts. Two works were published posthumously: several sections of the Prodromus (Volumes VIII–XI) and the Méemoire sur la famille des Myrtacées (1842).

Among the works published by Candolle are his complete revision of Lamarck’s Flore Françoise (1805, 1815); his Théorie élémentaire de la botanique, which first appeared in 1813 and was frequently republished; and his Cours de botanique (1827), which was republished several times. His early and well-deserved reputation, however, was due principally to his excellent monographs on extremely diverse families of plants, including those on the Leguminosae (1800), the Crassulaceae (1801), the Compositae (1810), the Cruciferae (1821), the Cucurbitaceae (1825), the Portulacaceae (1828), and the Cactaceae (1829). Candolle also published several superbly illustrated large works that are still considered classics, such as his four-volume work on the Liliaceae (1802–1808) with 240 plates by the fashionable painter Pierre Redouté, who had taught Marie Antoinette, and his book on the Leguminosae (1825).

Candolle’s most significant work was the Prodromus systematis naturalis regni vegetabilis, which was published in several sections from 1824 to 1839 and was continued by various collaborators after his death. The Prodromus is a huge botanical treatise that differs from those published previously because of Candolle’s far-reaching interests. In this work there are no dry descriptions of plants, such as were customary; instead the author, whose knowledge of botany was remarkable, treats all aspects of the science. The Prodromus contains allusions to problems of evolution as well as discussions, well in advance of the times, of ecology, phytogeography, biometry, and agronomy.

Candolle was fascinated by everything touching the world of plants, and not merely by taxonomy. Intrigued by questions of phytochemistry, he published papers including Observations sur une espèce de gomme qui sort des bûches du hêtre (1799), Examen d’un sel recueilli sur le Reaumuria (1804), and Notice sur la matière organique qui a coloré en rouge les eaux du lac de Morat (1826). He was interested in plant pathology, particularly in parasitic mushrooms, on which he wrote noteworthy memoirs in 1807 and 1817. Candolle was the first to analyze fossil mushrooms; in 1817 he published a valuable memoir on the genera Asteroma, Polystigma, and Stilbospora. Teratology was also one of his interests, but it was not until 1841 that he published his Monstruosités végétates. Doubtless due to the influence of Jean Sénebier, Candolle did extensive research in physiology; his most important works in this area are Premier essai sur la nutrition des Lichens (1797), Expériences relatives à l’influence de la lumière sur quelques végétaux (1800), Note sur la cause de la direction des tiges vers la lumière (1809), and De l’influence de la température atmosphérique sur le développement des arbres au printemps (1831).

Candolle was a pioneer in the science of agronomy, and some of his publications on this subject are still considered classics. His best works in the field include Mémoire sur la fertilisation des dunes (1803), Avis aux propriétaires de vignobles (1816), Premier rapport sur les pommes de terre (1822), Instruction sur l’emploi des engrais liquides (1825), Notice sur la culture de l’olivier (1825), Les pépinières du canton de Genève (1828), Considérations sur les forêts de la France (1830), and Essai sur la théorie des assolements (1831).

His early studies led Candolle to medical botany. He wrote numerous papers on pharmacology, of which the best-known are Recherches botanico-médicales sur les différentes espèces d’lpécacuanha (1802), Notice sur la racine de Caïnca, nouveau médicament du Brésil (1829), and Note sur l’huile de Ramtitlla (1833). He also summarized the pharmacological knowledge of the day in an outstanding treatise, Essai sur les propriétés médicales des plantes, comparées avec leursformes extérieures et classification naturelle (1804).

Candolle undoubtedly made his most original contribution to what was later known as phytogeography; he figures incontestably as a forerunner in this totally new science. Among his most noteworthy publications are Mémoire sur la géographie des plantes de France, considérée dans ses rapports avec la hauteur absolue (1817), Essai élémentaire de géographie botanique (1820), and Projet d’une flore physico-géographique de la vallée du Léman (1821). A worthy pupil of Lamarck, Candolle accurately describes the relationships between plants and soil, which affect the distribution of vegetation. He later had the opportunity to verify some of his “physico-geographical” theories while studying the flora of Brazil (1827), eastern India (1829), and northern China (1834).

Also an excellent biographer, Candolle left many notices of great value in the history of science; one of the best-known is La vie et les écrits de Fr. Huber (1832), which was translated into English by Silliman in 1833. He wrote also on political economy and statistics; a notable example is his classic memoir Sur la statistique du royaume des Pays-Bas (1830). In addition he was involved in education, administration, and public welfare.

BIBLIOGRAPHY

I. Original Works. Among Candolle’s major writings are Plantarum historia succulentarum, 28 secs. (1–20, Paris, 1799–1802; 21–28, Paris. 1803); Astragalogia (Paris. 1802);Les liliacées, 4 vols. (Paris. 1802–1808); Essai sur les propriétés médicales des plantes, comparées avec leurs formes extérieures et classification naturelle (Paris, 1804, 1816), trans, into German by K. J. Perleb (1818): Synopsis plantarum in flora gallica descriptarum (Paris, 1806); Icones plantarum Galliae rariorum (Paris. 1808); Théorie élémentaire de la botanique (Montpellier. 1813); Regni vegetabilis systema naturale, 2 vols. (Paris, 1817–1821); Pro-dromus systematis naturalis regni vegetabilis, 7 vols. (Paris, 1824–1839); and Cours de botanique: Organographie (Paris,1827), trans, into German by M. Meissner (Tübingen, 1827) and into English by M. Kingdon (London, 1839; New York, 1840).

II. Secondary Literature. On Candolle or his work, see J. Briquet, “Bibliographies des botanistes à Genève (1500–1931),” in Bericht der Schweizerischen botanischen Gesellschaft, 50 , sec. A (1940), 114–130; Alphonse de Candolle, Mémoires et souvenirs de A. P. de Candolle (Geneva, 1862); P. Gervais, Discours prononcé à l’inauguration du buste de M. de Candolle dans le jardin botanique (Montpellier, 1854); and A. de la Rive, Notice sur la vie et lesécrits de A. P. de Candolle (Geneva. 1851).

P. B. Pilet