Savigny, Marie-Jules-César Lelorgne De

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SAVIGNY, MARIE-JULES-CéSAR LELORGNE DE

(b. Provins, Brie, France, 5 April 1777; d. Versailles, France, 5 October 1851)

biology.

Savigny used his full name only on legal documents. His parents, Jean-Jacques Lelorgne de Savigny and Françoise Josèphe de Barbaud, had one other child, Amable Eléanore Louise Josèphe. Savigny studied at the local Collège des Oratoriens: his education there was supplemented by visits to the Génovéfains de Saint-Jacques. Besides classical languages, he was introduced to botany, the use of the microscope, and tales of travel. He was studying chemistry and botany with a local apothecary when, in 1793, he was chosen by a government commission to study in Paris. He enrolled at the École de Santé, attended lectures at the Muséum d’Histoire Naturelle, and became known to Lamarck, Daubenton, Cuvier, and Étienne Geoffroy Saint-Hilaire. Savigny’s mother, widowed and impoverished, joined him in Paris and died when he was twenty.

Savigny was about to begin a teaching career in botany when Cuvier urged him to join Napoleon’s expedition to Egypt as a zoologist: he would study invertebrates while Geoffroy Saint-Hilaire studied vertebrates. With many other scholars, they remained in Egypt from June 1798 until January 1802. Savigny then returned to France and spent the rest of his life in Paris and Versailles, with the exception of an excursion to Italy between February and November of 1822. (Pallary first put this trip during the period 1817–1822 [“;Vie,” 45] but later found letters that show the visit to have been briefer [“;Documents,” 90, 101].) Beginning about 1817, Savigny suffered from a severe nervous affliction (not blindness) that made visual work, and even thought, impossible. His life as a scientist had virtually ended by the time he was elected to the Académie des Sciences in 1821. When the commission responsible for publishing the results of the Egyptian expedition finally despaired of receiving his promised descriptions, they corresponded with Savigny’s devoted mistress. Agathe-Olympe Letellier de Sainteville. She seems to have helped effect a compromise: plates drawn under Savigny’s supervision were eventually published in Description de l’Égypte, with notes written by Victor Audouin.

Savigny’s Mémoires sur les animaux sans vertèbres (1816) deeply impressed his contemporaries and was cited as a model of fine zoology for the next fifty years. By example rather than by precept, he demonstrated the value of comparative morphology. Presumably it was his botanical training that led him to seek, in the insects and crustacea collected in Egypt, “perfectly Linnaean characters, that is, where the same organs are always disposed in the same order, and can be compared without interruption” (Mémories sur les animaux sans verièbres, iii).

Just as flowers were analyzed into calyx, corolla, stigma, and style, so Savigny analyzed insect mouthparts into labrum, mandibles, maxillae, and labium. Previous zoologists had distinguished Lepidoptera, for example, by the absence of regular mouthparts and the presence of a two-part coiled tubule. Savigny interpreted the tubule as a highly modified pair of maxillae and said that the other mouthparts, however minute. were present , Saigny extended his comparison to the appendages of crustacea and other arthropods, to the point of seeing the mourthparts of the horseshoe crab as homologous to the legs of insects. In the second part of the Mémories, he compared the anatomy of solitary ascidians with that of various zoophytes, demonstrating that the latter should be regarded as colonial ascidians. He even suggested some homologies between ascidians and salps.

While Savigny was showing unsuspected homologies among these invertebrates, Geoffroy Saint-Hilaire was doing the same with the bones of repriles and fish. Savigny’s work encouraged Geoffroy Saint-Hilaire to search for homologies between vertebrates and arthropods. Savigny did not discuss principles or suggest a “unity of plan,” but his work became a model for the morphological zoology that flourished in the nineteenth century.

BIBLIOGRAPHY

I. Original Works. Savigny’s principal works are L’histoire naturelle et mythologique de l’ibis (Paris, 1805); Mémoires sur les animaux sans vertébres (Paris, 1816); Description de l’Égypte, publiée par les ordres de sa majesté l’Empereur Napoléon-le-Grand. Histoire naturelle (Paris, 1809-[1826]). which includes “Systéme des oiseaux de l’Égypte et de la Syrie” (1809), “SystÉme des annélides, principalement de celles des cótes de l’Égypte et de la Syrie” (1820), and celles des already published material on the ibis and on ascidians; and “Remarques sur certain phénoménes dont le principe est dans l’organe de la vue, ou fragments du journal d’un observateur attient d’une maladie des yeux,” in Mémoires de l’Académie des sciences de l’Institut de France18 (1842), 385–416.

II. Secondary Literature. On his life and work, see Paul Pallary, “Marie Jules-César Savigny: sa Vie et son Oeuvre: la Vie de Savigny,” in Mémoires, Institut d’Égypte17 (1931), 1–111; “L’oeuvre de Savigny”, ibid., 20 (1932), 1–112, with bibliography. 88–92; and “Documents,” ibid., 23 (1934), 1–203.

Mary P. Winsor