RUDOLPHI, KARL ASMUND

(b. Stockholm, Sweden, 14 July 1771; d. Berlin, Germany, 29 November 1832)

anatomy, physiology, helminthology.

Rudolphi was the son of the vice-rector of the German school in Stockholm, where he spent his early years. He studied philosophy, natural sciences, and medicine at Greifswald, from which he graduated in philosophy in 1793 and in medicine, with a dissertation on intestinal worms, in 1794. In 1801, having finished a course at the Berlin Veterinary School, he returned to Greifswald, first as professor in the veterinary institute, then, in 1808, as professor of medicine in the medical faculty. In 1810 he was appointed to the chair of anatomy and physiology at the newly established University of Berlin; he became one of the most influential members of the university, and remained there for the rest of his life.

Some of Rudolphi’s early work was in botany. In 1805 he shared an award from the Göttingen science society with his friend H. F. Link, with whom he established a new direction in the study of plant morphology. Rudolphi carried out a careful examination of all parts of a number of species of plants at all stages of their growth and concluded that without exception each plant consists wholly of cellular tissue in the early stages of its development and in large part of cellular tissue at the later stages of its growth. This constituted an important first step toward the recognition of the cell as the basic unit of the structure of plants. Rudolphi was, on the other hand, criticized for his erroneous assertion that mushrooms differ so greatly in their structure from other plants that they do not belong to the plant kingdom.

Rudolphi also did pioneering work in helminthology, which he developed as a special branch of zoology. In the course of making several thousand observations he identified and described a large number of new species of worms parasitic in both animals and man. (In 1803 Zeder had listed 391 species; Rudolphi in 1819 catalogued 993.) In his masterful and detailed description of the structure and life cycle of parasitic worms, Rudolphi established the basis for all subsequent systematic research on these animals. He nonetheless believed that these parasites are generated by disease in the body of the host, even though his predecessor P. S. Pallas had tried to demonstrate that their eggs enter the body of the host from outside. And although his work on helminthology was widely influential, Rudolphi’s attempt at more general zoological classification was both unsuccessful and soon forgotten.

Among Rudolphi’s works in comparative anatomy, his studies of intestinal villi in vertebrates were especially important because they constituted both a contribution toward Bichat’s tissue theory and a demonstration of the utility of the microscope in the investigation of animal morphology. These examinations were among the first in the new field of comparative histology.

Rudolphi’s textbook on physiology, Grundriss der Physiologie, was also widely influential, although he had completed only two volumes at the time of his death. It was based upon Rudolphi’s own experience, particularly in comparative anatomy, and served as a useful counterforce to the romantic and speculative physiology then prevailing in Germany. (Müller even mentioned the brevity with which Rudolphi treated any subject to which he could not add critical comment or new information at first hand.) In the general section of his textbook Rudolphi took an anthropological view of physiology, stressing the differences between man and the great apes. His simple and concise grouping of tissues was valuable. He gave a clear and realistic account of the functions of various parts of the body, which in general agreed with modern conceptions.

Rudolphi repudiated the fantastic conceptions of life put forward by Schelling and Oken, and likewise dismissed speculations about symmetry and Stahl’s notion of the soul as being the cause of bodily phenomena. The idea of the soul or mind, he pointed out, does not contribute to the understanding of physiology; in a study of the cerebral cavities he cited the entire brain as being the organ of intelligence—in opposition to Sömmering, who located intellect in the cerebrospinal fluid—and indicated that such complex processes as thought and reasoning must arise from a complex structure. Although he rejected many of the more mystical notions of science—including Gall’s phrenology, Blumenbach’s nisus formativus, and Cuvier’s theory of catastrophes—Rudolphi supported the “animal chemistry” of Berzelius, with whom he was in personal touch, and included his discoveries and views in his own physiology.

Rudolphi was to some degree hampered in his physiological investigations by his reluctance to perform experiments upon living animals. He advocated more humane experimentation and based most of his own work on his studies in comparative anatomy, emphasizing the relationships between structure and function. He stressed the importance of chemistry as well and insisted upon the primary role of the exact sciences in medical training and practice, thereby giving impetus to the inductive and empirical physiology and medicine that had begun to develop at the University of Berlin. He was an inspiring teacher and was often of aid to younger scientists, both in Germany and abroad. He traveled in a number of European countries and corresponded with foreign scientists, particularly Scandinavians; he influenced and helped Baer, Purkyně, Müller, Siebold, Nordmann, and Lovén, among others. He was an important figure in the transition from romantic science to the modern approach in biology and medicine.

Rudolphi was also a collector of medallic portraits of physicians and scientists. His index of his collection, especially in C. L. Duisburg’s final enlarged 1862 edition, became a standard work in this special branch of numismatics.

BIBLIOGRAPHY

I. Original Works. Johannes Müller, “Gedächtnisrede auf Carl Asmund Rudolphi,” in Abhandlungen der Königlichen Akademie der Wissenschaften zu Berlin, Physikalische Klasse (1837), xvii–xxxviii, contains a bibliography of sixty-five titles of Rudolphi’s work, including Entozoorum, slve vermium intestinalium, historia naturalis, 2 vols. (Amsterdam, 1808–1810); Beiträge zur Anthropologie und allgemeine Naturgeschichte (Berlin, 1812); Entozoorum synopsis (Berlin, 1819); Grundriss der Physiologie, 2 vols. (Berlin, 1821–1828); and Index numismatum in virorum de rebus medicis vel physicis meritorum memoriam percussorum (Berlin, 1823).

II. Secondary Literature. In addition to Müller, cited above, on Rudolphi and his work see his colleague H. F. Link, “Nachricht von dem Leben des Königl. geh. med. Raths und Professors K. A. Rudolphi,” in Medizinische Zeitung, 2 (1833), 17–20, the first appreciation of his career. More recent works are M. Dittrich, “Die Bedeutung von Karl Asmund Rudolphi (1771–1832) für die Entwicklung der Medizin und Naturwissenschaften im 19. Jahrhundert,” in Wissenschaftliche Zeitschrift der Universität Greifswald, Math.-naturwiss. Reihe, 16 (1967), 249–277; E. Nordenskiöld, The History of Biology (New York, 1928), 352–355; A. Waldeyer, “Carl Asmund Rudolphi und Johannes Müller,” in Forschen und Wirken. Festschrift zur 150 Jahr-Feier der Humboldt-Universität zu Berlin, I (Berlin, 1960), 97–115; and W. Waldeyer, in Biographisches Lexikon der hervorragenden ärzte, 2nd ed., IV (Berlin–Vienna, 1932), 911–913.

Vladislav Kruta