Agardh, Carl Adolph

(b. Bastad, Sweden, 23 January 1785; d. Karlstad, Sweden, 28 January 1859)

botany.

Agardh’s fame is based on his contributions to the taxonomy of algae, but his scientific interests covered a far wider area. In many ways he reflects the philosophic romanticism that flourished when he was a professor at the University of Lund (1812–1835).

In Sweden, where Linnaeus had been active until 1778, as well as abroad, knowledge of algae and their classification was still rudimentary at the beginning of the nineteenth century. Linnaeus had divided the algae known to him into three families (Fucus, Ulva, Conferva), and after his death botanists continued to incorporate new forms into the same groups. In 1812 the French botanist Lamouroux took an important step toward a more comprehensive and natural differentiation. especially among the red algae, but a new understanding of the relationships existing within the larger groups of algae was first presented in Agardh’s Synopsis algarum Scandinaviae(1817). Although it dealt basically with only one limited regional flora, the introduction presented an entirely new systematic survey of everything then considered algae. Agardh’s broad outline became the Species algarum(1821–1828), which was never finished, and the more concentrated Systema algarum(1824), which summarized the state of algology at that time with precise groupings and clearly defined descriptions. In these works, with a collection of illustrations, he presented theories that are still considered nodal points in the development of algology. He achieved eminence partly through fieldwork, but he acquired a thorough knowledge of the literature and an extensive knowledge of various collections (among others, the herbaria of algae in Paris, which he examined in 1820–1821), It was not until 1827 that he undertook an extensive field trip to the north shore of the Adriatic Sea, where he became familiar with the little-known algal flora.

Although Agardh is remembered mainly as an algologist, he represents several of the main trends in botany at that time. He took an active part in contemporary discussions of the natural system of plant classification. Agardh presented his outline of the plant kingdom in his Aphorismi botanici, in the form of sixteen academic dissertations (1817–1826), and Classes plantarum(1825), in which he characterized several new plant families, some of which are still considered valid. His opinions reflect the views of nature developed by German Romantic Naturphilosophen: Schelling, Oken, and Nees von Esenbeck, Agardh, however, opposed the deductive, speculative method of the Romantics. He insisted that all study of nature had to be approached inductively, that it is not possible to establish a few groups within which all species can be classified, He believed that attention must be focused on the individual species and genera, which step by step, and with great care, might be arranged in larger groupings whose mutual relationships could be established only by further research But in his plea for caution he expounded the Romantic Naturphilosophie. Nature is freedom; therefore it does not obey human logic, but its own logic, which cannot be penetrated by reason. Thus, no deductive, logically functioning system of classification can conform to the laws of nature.

Agardh’s romanticism was even more pronounced in his writings on plant anatomy and plant physiology. On his way home from the Adriatic he stopped at the mineral springs of Karlsbad, where he met the Romantic philosopher Schelling. Together they studied algal forms in the hot springs, and Agardh demonstrated their life cycle. He later called his visit to Karlsbad “the most interesting days of my life”; it is evident that his interests here shifted from taxonomy to the problems of plant life. He first published his views on this subject in several articles in French, and then in a more extensive form in Lärobok i botanik (1830–1832), which was translated into German and dedicated to Schelling. The general tenor of the manual, and in particular the importance that Agardh attributes to chemistry, led to a violent disagreement with his friend Berzelius. Their animated correspondence on this subject reveals a strong contrast between a romantic, speculative temperament and an empirical one.

Agardh had divided personal aims and was often quite disturbed. He found himself increasingly at odds with his academic surroundings. He was, however, politically active, made important contributions to economics, and participated in pedagogical and theological debates.

In 1835 Agardh was offered the bishopric of the Karlstad diocese in western Sweden, which he accepted, and thereupon gave up writing on botany.

BIBLIOGRAPHY

I. Original Works. A complete bibliography of Agardh’s writings can be found in both J. E. Areschoug and A. B. Carlsson (see below). His works include Synopsis algarum Scandinaviae (Lund, 1817) Aphorismi botanici (Lund, 1817–1826); Species algarum, 1, pt. 1 (Greifswald, 1821); I, pt. 2 (Lund, 1822); II, pt. 1 (Greifswald, 1828); Systema algarum (Lund, 1824); Classes plantarum (Lund, 1825); and Lärobok i botanik (Malmö, 1830–1832). His correspondence with Berzelius is in H. G. Soderbaum’s ed. of Berzelius’ letters, Jac. Berzelius’ brev, X (Uppsala, 1925). His unpublished correspondence is mainly in the library of the University of Lund.

II. Secondary Literature. Two articles on Agardh, both in Swedish, are J. E. Areschoug, “Carl Adolph Agardh,” in Levnadsteckningar över Kungliga Svenska Vetenskapsakademiens ledarnlöer, I (Stockholm, 1869–1873): and A. B. Carlsson, Svenskt biografiskt lexikon, I (Stockholm, 1917–1918).

Gunnar Eriksson