(b. Mulhouse, France, 29 September 1825; d. Paris, France, 13 July 1905)
After completing his education at the École Polytechnique, Schlumberger joined the navy corps of engineers at Toulon in 1849. His transfer in 1855, to Nancy, where he was in charge of purchasing timber, enabled him to make many field trips and to develop an interest in natural history, which dated from his youth. The collecting of fossils, combined with his acquaintance with Olry Terquem, led to his career as a micropaleontologist specializing in Foraminifera.
In 1879 Schlumberger went to Paris; and although he was promoted a few years later to the rank of chief engineer, he requested early retirement and became a guest scientist at the laboratory of paleontology of the Muséum d’Histoire Naturelle and later at the École des Mines. About 1882 he began his collaboration with E. Munier-Chalmas, who had just recognized dimorphism in Nummulitids. By means of a new thin-section technique developed by Schlumberger, both men were able to discover the same character among Miliolidae, as well as important features pertaining to their apertures.
By 1894 dimorphism in Foraminifera had been recognized by many as an extremely widespread character and had been explained by alternating phases of sexual and asexual reproduction. Unfortunately, Schlumberger was not active in this final development and interpretation of some of his original discoveries because Munier-Chalmas’s reluctance to write papers in final form had gradually brought their collaboration to a standstill. Consequently Schlumberger continued his research on other groups of Foraminifera alone. He wrote in particular a series of important papers on the stratigraphic distribution of Orbitoids. After the death of Munier-Chalmas and during the last years of his life, he resumed his studies on Miliolidae.
Despite his lack of formal scientific training, Schlumberger contributed in a fundamental manner to the solution of one of the most puzzling problems of micropaleontology.
Schlumberger’s writings include “Note sur les Foraminifères”, in Feuille des jeunes naturalistes, 12 (1882), 83–112; “Nouvelles observations sur le dimorphisme des Foraminifères”, in Comptes rendus... de l’Acadé-mie des sciences, 96 (1883), 862–866, 1598–1601, written with E. Munier-Chalmas, also in English as “New Observations on the Dimorphism of the Foraminifera”, in Annals and Magazine of Natural History, 5th ser., 11 (1883), 336–340; “Sur les Miliolidées trématophorées, lère partie”, in Bulletin de la Société géologique de France, 3rd ser., 13 (1885), 2737–323; “Révision des Biloculines des grands fonds, expéditions du Travailleur et du Talisman”, in Mémoires de la Société zoologique de France, 4 (1891), 155–191; “Monographie des Miliolidées du golfe de Marseille”, ibid., 6 (1893), 199–222; “Première note sur les Orbitoïdes (Orbitoides, s. str.).”., in Bulletin de la Société géologique de France, 4th ser., 1 (1901), 459–467; “Deuxième note sur les Orbitoides (Orbitoides, s. str.).” ibid., 2 (1902), 255–261; “Troisième note sur les Orbitoides (Orthophragmina discoides)”, ibid., 3 (1903), 273–289; “Quatrième note sur les Orbitoides (Orthophragmna étoilés)”, ibid., 4 (1904), 119–135; and “Deuxiè,e note sur les Miliolidées trématophorées”, ibid., 5 (1905), 115–134.
A complete list of Schlumberger’s publications is in H. Douvillé, “Charles Schlumberger, notice nécrologique”, in Bulletin de la Société géologique de France, 4th ser., 6 (1906), 340–350.
Albert V. Carozzi