SIEBOLD, CARL THEODOR ERNST VON

(b. Würzburg, Germany, 16 February 1804; d. Munich, Germany, 7 April 1885)

medicine, zoology.

Siebold was the third child of Elias von Siebold, professor of medicine and midwifery at Würzburg, and Sophie von Schäffer. His happy childhood was punctuated by fondly remembered vacations in Regensburg at the home of his grandfather Jakob Christian Gottlieb von schäffer, whose extensive natural history collection first stimulated Siebold’s interest in the subject. Siebold accompanied his older brother Eduard (who later became professor of medicine and midwifery at Marburg and then at Göttingen) and their friend Ignaz Döllinger on entomological and botanical excursions in the woods near Würzburg. In a short autobiography Siebold wrote of his friendship with Döllinger:

This relationship gave me the opportunity one day to enter the study of Döllinger’s father, the famous founder of embryology. And it was there that I glimpsed a saucer filled with black wax placed on a desk near the window: a flea was affixed to the saucer with needles so that the arrangement of its intestines could easily be examined. This anatomical preparation made a deep and lasting impression on me.

Siebold began his schooling in Würzburg and continued it at the Gymnasium zum Grauen Kloster in 1816, when his father assumed a post at the University of Berlin. During these years Siebold collected and identified butterflies and dug up newts, snails, and mussels. He passed the final secondary school examination in the fall of 1823 and, acceding to his father’s wishes, began to study medicine, although even at this early date he would have preferred to devote himself exclusively to zoology. He spent the first two semesters of his medical studies at Berlin, attending the lectures of Karl Martin Lichtenstein, Link, and Rudolphi, among others. In the fall of 1824 he went to Göttingen, where his interest in natural history was encouraged by Blumenbach and Johann Hausmann. Three years later he returned to Berlin, and on 28 April 1828 received the M.D. The sudden death of his father on 12 July 1828 obliged Siebold to find some means of support. Accordingly, he prepared to practice medicine, passing the two official qualifying examinations in 1829 and 1830. In the spring of 1831 he was named district physician in Heilsberg (now Lidzmark). On 10 April 1831, shortly before assuming his duties, he married the twenty-six-year-old Fanny Nöldechen.

In Königsberg, en route to Heilsberg, Siebold met Karl Ernst von Baer, who offered him guidance and assistance in his scientific studies during the next three years by sending him technical literature and information. Siebold’s wish to be near a university again was fulfilled by his transfer in 1834 to the post of municipal physician in Königsberg. He still hoped for the opportunity to qualify as a university lecturer, and within a few months it seemed that he would have his chance. Both Baer, who had received a post in St. Petersburg, and Lichtenstein supported Siebold’s candidacy at Albertus University, but their efforts were futile— ruling dating to 1544 prohibited Catholics from teaching there.

Following this disappointment Siebold accepted a post in the same year (1834) in Danzig as municipal physician and director of a school of midwifery. His investigations during this period on the phenomena of generation in jellyfish, intestinal worms, and insects can be viewed as preliminary studies for Steenstrup;s fundamental work on the alternation of generations (1842). Siebold also published extensively on invertebrates of Prussia.

Siebold’s many publications soon attracted the attention of zoologists. No less a figure than Alexander von Humboldt—who was a guest at Siebold’s house in Danzig on 12 and 13 September 1840—intervened successfully with King Ludwig I of Bavaria in favor of Siebold’s appointment to the chair of zoology and comparative anatomy at the Friedrich Alexander University in Erlangen, left vacant by the departure of Rudolph Wagner. On 1 March 1841 Siebold returned with his family to his native Franconia. In addition to his regular lectures. Siebold also taught veterinary medicine, physiology, and histology, requiring his students to use the microscope. At the beginning of 1845 Siebold accepted an offer from the University of Freiburg, and on 28 October 1845 he was formally welcomed by the university senate.

Siebold developed a close friendship at Freiburg im Breisgau with the botanist Alexander Braun, who accompanied him in 1847 to the congress of Swiss scientists at Schaffhausen. On this occasion Siebold realized a long-cherished plan: he and Braun agreed to join with Naegeli and Koelliker in editing a new journal of botany and zoology. Various circumstances, including Braun’s election to the office of vice-chancellor of the University of Berlin and Naegeli’s departure for Freiburg, prevented the journal from appearing in the form originally envisioned. Instead, Siebold and Koelliker created the Zeitschrift für wissenschaftliche Zoologie, first published in 1848. In the same year Siebold completed his Lehrbuch der vergleichenden Anatomie der wirbellosen Thiere, begun in 1845 and one of the most important systematic reforms since the work of Cuvier. In it Siebold divided the Radiata into groups and characterized the Protozoa as single-celled organisms.

The political disturbances of 1848 led Siebold, in the spring of 1850, to Breslau, where he succeeded Purkynê as professor of physiology. At Breslau, Siebold continued his research on the development of the Cestoda and discovered the parthenogenesis of the honeybee. Wagner considered the discovery of parthenogenesis to be “one of the most disconcerting obstacles impeding the formulation of so-called general laws of animal life processes.” Siebold remained at Breslau for only two years. Disappointed with the university, he was delighted when the Bavarian ministry of education in June 1852 began negotiations concerning his assuming the professorship of physiology and comparative anatomy at Munich. The discussions lasted until the late fall, but on 26 November Siebold informed the dean of the Breslau medical faculty that he had accepted the post.

Siebold became a member of the medical faculty of the Ludwig Maximilian University in Munich on 13 April 1853: and on 18 January 1854 he was accepted as a member of the Bavarian Academy of Sciences, of which he had been a corresponding member since 1848. According to the terms of Siebold’s contract, he was required to establish an institute of physiology in Munich. Thus he lectured on both zoology and physiology only until he was able to relinquish the chair of physiology, along with the post of curator of the anatomical institute, to Theodor Bischoff. Siebold’s lectures encompassed zoology, comparative anatomy, the reproductive biology of man and animals, and parasitology. He also was curator of the Bavarian state collections of comparative anatomy, physiology, and zoology.

While in Munich, Siebold completed Über die Band-und Blasenwürmer nebst einer Einleitung über die Enstehung der Eingeweidewürmer and actively participated in the research of his student Bilharz. Siebold’s most important topic of research, however, was parthenogenesis: and in 1856 he published Wahre Parthenogenesis bei Schmetterlingen und Bienen. In addition, he obtained a royal contract (dated 3 May 1854) to produce a monograph on the fishes of Central Europe, a task that required extended travel and an intensive study of the specialized literature. The result of nine years’s work, Die Süsswasserfische von Mitteleuropa, illustrated with sixty-four woodcuts and two colorplates, finally appeared in 1863.

Siebold’s wife died on 26 December 1854, one of the last victims of the cholera epidemic. A year later, in Göttingen, Siebold married her younger sister. Antoynie Nöldechen. Siebold was acquainted with artists and scholars, and she made their home a center of stimulating social gatherings. He also belonged to the Munich poets’s circle, whose members were regularly guests of the king.

At a congress of German scientists and physicians in Königsberg in 1860, Siebold met the young Ernst Haeckel, with whom he felt closely united in discussions of the Darwinian theory of evolution. Their common enthusiasm provided the basis of a lifelong correspondence and friendship. In a letter to Haeckel on his fortieth birthday, the seventy-year-old Siebold wrote.

Oh, how I wish I could see this reform carried through! For I must tell you that brilliant though it is, it is not easy for a zoologist trained in the old school. Instead of being able to relax in my later years, I have to learn just as much—no, even more—than I did during all my younger days. If you reflect that in old age it is much harder to learn than to forget, you will bear with me.

At the end of the winter semester of 1882–1883, during which he gave a two-hour lecture course, Siebold submitted his request for retirement. In a birthday letter to Haeckel dated 18 February 1883, he confessed: “I have been much upset recently by the fact that in my lectures, which I was accustomed to give without the aid of notes, I cannot always remember the scientific names of animals with their genus and species designations—this causes me the greatest embarrassment,” Ludwig II granted him permission to retire on 11 March 1883, two years before his death.

BIBLIOGRAPHY

I. Original Works. Siebold’s works include Observationes quaedam de Salamandris et Tritonibus (Berlin, 1828), his M.D. thesis: “Über die Spermatozoen der Crustaceen, Insecten, Gastropoden und einiger anderer wirbelloser Thiere,” in Archiv für Anatomie. Physiologie und wissenschaftliche Medicin. 3 (1836), 13–53; “Fernere Beobachtungen über die Spermatozoen der wirbellosen Thiere,” ibid., 232–255; “Fernere Beobachtungen über die Spermatozoen der wirbellosen Thiere, 3. Die Spermatozoen der Bivalven, 4. Die Spermatozoen in den befruchteten Insecten-Weibchen,” ibid., 4 (1837). 381–439; “Zur Entwicklungsgeschichte der Helminthes,” in K. F. Burdach. ed., Die Physiologic als Erfahrngswissenschaft. II (Leipzig, 1837), 183–213; “Beiträge zur Naturgeschichte der wirbellosen Thiere. Über Medusa, Cyclops, Loligo, Gregarina und Xenos,” in Neueste Schriften der Naturforschenden Gesellschaft in Danzig3 (1839), 1–94; Observationes quaedam entomologicae de oxybelo uniglume atque miltogramma conica (Erlangen, 1841); and Viro simmer reverend collegate... (Erlanger, 1884).

Later writings are “Parasiten,” in R. Wagner, ed., Handwörterbuch der Physiologies mit Rücksicht auf physiologische Pathologie, II (Brunswick, 1844), 641–692; Lehrbuch der vergleichenden Anatomie der Wirbellosen Thiere (Berlin, 1848); “Über den Generationswechsel der Cestoden nebst einer Revision der Gattung Tetrarhynchus,” in Zeitschrift für wissenschaftliche zoologie, 2 (1850), 198–253; Übe die Band-und Blasenwürmer nebst einer Einleitung über die Entstehung der Eingeweidewürmer (Leipzig, 1854); Wahre Parthenogenesis bei Schmetterlingen und Biene. Ein Beitrag Zur Fortplfanzungsgeschichte der Thiere (Leipzig, 1856); Über Parthenogenesis (Munich, 1862); Die Süsswasserfische von Mitteleuropa (Leipzig, 1863); and Beiträage zur Parthenogenesis der Arthropoden (Leipzig, 1871).

A short autobiography. used by A. Koelliker for his biographical sketch, is still extant in MS in a private collection in Freiburg im Breisgau.

II. Secondary Literature. On Siebold and his work. see E. Ehlers, ’Carl Theodor Ernst von Siebold. Eine biographische Skizze,” in Zeitschrift für wissenschaftliche Zoologie, 42 (1885), i–xxiii; R. Hertwig, Gedächtnisrede auf Carl Theodor von Siebold gehalten in der öffentlichen Sitzung der k. Bayerischen Akademie der Wissenschaften... (Munich, 1886); A. Koelliker, “Carl Theodor von Siebold, eine biographische Skizze,” in Zeitschrift für wissenschaftliche Zoologie. supp. 30 (1878), v–xxix; H. Körner, “Die Würzburger Siebold. Eine Gelehrtenfamilie des 18. und 19. Jahrunderts,” in Deutsches Familienarchiv, nos, 34–35 (1976), 451–1080; G. Olpp. Hervorragende Tropenärzte in Wort und Bild (Munich, 1932), 378–379; and F. Winckel, “Carl Theodor Ernst von Siebold,” in Allgemeine deustsche Biographie, XXXIV (1892), 186–188.

Armin Geus