MAUPAS, FRANçOIS ÉMILE

b. Vaudry, Calvados, France, 2 July 1842; d. Algiers, Algeria, 18 October 1916)

zoology, biology.

The son of Pierre-Augustin Maupas, deputy mayor of Vaudry, and of Marie Adèle Geffroy, Maupas attended the municipal secondary school and then entered the École des Chartes. In 1867 the became archivist of the Department of Cantal, where he developed an interest in natural science and, in particular, in free protozoans. He spent his vacations in Paris in order to work in the laboratories of the Muséum d’Histoire Naturelle and of the Sorbonne. In 1870 Maupas was appointed an archivist in Algiers and then curator of the Bibliothèque Nationale. In his leisure moments he pursued research in zoological microscopy at home with rudimentary instruments. Maupas never married, and he lived the life of an isolated researcher. On 27 June 1901 he was elected a corresponding member of the Academy of Sciences, and in 1903 he received an honorary doctorate from the University of Heidelberg.

Maupas’s scientific work was devoted entirely to sexuality and reproduction among the protozoans, rotifers, nematodes, and oligochaetes, which he studied with the aid of extremely ingenious breeding and culture techniques. Among the ciliates he investigated cultures bearing on hundreds of generations. He carefully examined the phenomenon of conjugation, which he discovered, and demonstrated the overall unity of the process and of its secondary features. He likewise analyzed the transformations of the nucleus. Maupas at first believed that this phenomenon effected a rejuvenation of the offspring after a long period of multiplication theta produced a fatal aging—a view contradicting Weismann’s theories on the “immortality” of the infusorians. His observations were later confirmed by other protistologists—who showed, however, that senescence does not have the absolute and inevitable character that Maupas had attributed to it. He also demonstrated that there are two categories of females in the rotifers: those which are parthenogenetic, producing only females, and those which can also be fertilized. If the latter are not impregnated, they yield only males; if they are fertilized they will produce special eggs which undergo later development and always produce females.

Among the nematodes, Maupas studied free and parasitic species. Among the free forms (Rhabditida) he showed that the postembryonic development consisted of five stages, of which the fifth is the adult stage (Maupas’s law); and he demonstrated that in the parasitic forms the third stage, which is part of the molt of the second, is the infesting form. He provided more precise data on the phenomenon of encystment and studied parthenogenesis and hermaphroditism with self-fertilization, as well as cross-fertilization. These investigations earned him the Grand Prize in physical sciences of the Institut de France (1901). With L. G. Seurat he made observations on the strongyles, parasitic nematodes which are agents of bronchopneumonia in sheep in Algeria, and specified the etiology of this disease. Some of Maupas’s investigations of the nematodes were published posthumously (1919). He also worked on freshwater oligochaetes (Nais, Dero, Pristina, Aelosoma), of which he obtained cultures prolonged for several months.

A complete naturalist, Maupas also published geological and botanical observations. In addition, he translated important German scientific works. Maupas was virtually unique among biologists of the second half of the nineteenth century in his ability to produce fundamental zoological work, without scientific training and through work in isolation with incredibly simple means and no real laboratory or collaborators.

BIBLIOGRAPHY

I. Original Works. Maupas’s principal publications are “Contribution à l’ étude morphologique et anatomique des infusoires ciliés,” in Archives de zoologie expérimentale et générale, 2nd ser., 1 (1883), 427–664; “Recherches expérimentales sur la multiplication des infusoires ciliés,”p ibid., 6 (1888), 165–277; “Sur la multiplication agame de quelques métazoaires inférieurs,” in Comptes rendus… de l’s Académie des sciences, 109 (1889), 270–272; “Le rajeunissement caryogamique chez les ciliés,” in Archives de zoologie expérimentale et générale, 2nd ser., 7 (1889), 149–517; “Sur la fécondation de l’ Hydatina scuta,” in Comptes rendus…de l’ Académie des sciences, 111 (1890), 505–507; “Sur la multiplication et la fécondation de l’Hydatina scuta,” ibid., 310–312; “Sur le déterminisme de la sexualité chez l’ Hydatina scuta,” ibid., 113 (1891), 388–390; “La mue et l’ enkystement chez les nématodes,” in Archives de zoologie expérimentale, 3rd ser., 7 (1900) 563–632; “Modes et formes de reproduction des nématodes,” ibid., 8 (1901), 463–624; “Sur le mécanisme de l’accouplement chez les nématodes,” in Comptes rendus…de laSociété de biologie, 79 (1916), 614–618, written with L. G. Seurat; “Essais d’hybridation chez les nématodes,” in Bulletin biologique de la France et de la Beligique, 52 (1919), 467–486; and “Expériences sur la reproduction asexuelle des oligochétes,” ibid., 53 (1919), 150–160.

Among Maupas’s translations is H. Burmeister, Histoire de la création (Paris, 1879).

II. Secondary Litereature. See M. Caullery, Inauguration de la plaque commémorative apposée sur la maison habitée par Émile Maupas à Alger,le mecredi 6 avril 1932 (Paris, 1932), with portrait; and E. Sergent, “Émile Maupas prince des protozoologistes,” in Archives de l’Institue Pasteur d’ Algérie, 33 (1955), 59–70.

Jean ThÉodoridÉs