(b. Brive-la-Gaillarde, France, 29 November 1762; d. Paris, France, 6 February 1833),
Latreille was the natural son of J.-B.-J . Damazit de Sahuguet, baron d’Espagnac, a high-ranking officer in the French army. The identity of his mother is unknown. He was raised by foster parents, but his father provided for much of his education and in 1778 arranged for him to go to the Collège Cardinal Lemoine in Paris. Latreille received the degree of maître ès arts at the University of Paris in 1780. He then prepared for the priesthood and was ordained in 1786, but his intended ecclesiastical career was cut short by the Revolution.1 In 1795 he attended the École Normale de Paris.
Frail in constitution throughout his life, Latreille had been encourged at an early age to pursue natural history as a means of strengthening his health. He took up this activity eagerly, and by the 1790’s he had achieved sufficient recognition as a naturalist to be elected an associate, or corresponding, member of the Société d’Histoire Naturelle de Paris (1791), the Société Philomathique de Paris (1795), and the First Class of the Institut de France (1798). Although he was considered one of the foremost entomologists of the day, Latreille spent most of his career in subordinate positions which earned him only a meager existence. In 1798 he went to the Muséum d’Histoirre Naturelle in Paris as organizer of its entomological collection. There he officially assumed the role of aide-naturaliste in 1805, serving as demonstrator in Lamarck’s course in invertebrate zoology. He eventually took over Lamarck’s course in 1820, when Lamarck became completely blind. III health later forced Latreille to cede some of these responsibilities to Jean Victor Audouin. Following Lamarck’s death in 1829, the chair of invertebrate zoology was divided into two, and Latreille became professor in the new chair of entomology. In addition to his work at the Muséum d’Histoire Naturelle, he taught briefly at the École Vétéinaire d’Alfort (1814-1815). He was named a member of the Institut de France in 1814 and received the decoration of the Légion d’Honneur in 1821. Although known primarily for his entomological studies, he wrote on a wide range of zoological subjects as well as ancient geography and chronology.
Latreille’s major scientific contribution lay in applying the “natural method” to the classification of the insects, arachnids, and crustaceans. This task was undertaken at a time when entomological knowledge and collections were undergoing a spectacular growth (from an estimated 1,500 specimens in 1789 the collection at the Muséum d’Histoire Naturelle grew to roughly 40,000 specimens representing 22,000 species in 1823).2 Linnaeus and Fabricius had constructed artificial systems for classifying the insects, the former relying primarily upon the number and configuration of the wings and the latter relying exclusively on the parts of the mouth. Latreille’s goal in his first major work, his Précis of 1796, was to arrange the genera of insects in their “natural order” by taking numerous characters into consideration. His system was based essentially upon a combination of the characters that Linnaeus and Fabricius had employed.
Latreille’s most significant work, the four-volume Genera crustaceorum et insectorum (1806-1809), was developed along the same lines. While Latreille praised Cuvier for having founded zoological classification on comparative anatomy, he based his own classificatory work primarily on the consideration of external characters. Nonetheless, as one of his successors remarked more than half a century after the appearance of the Genera, the work offered “such and exact exposition of the characters of the insects, arachnids, and crustaceans, and nearly always such a just appreciation of the natural affinities of these animals, that the most modern researches have only added rectifications of a second order.” 3
Unlike such notable predecessors as Réaumur and Fabricius, Latreille presented a balanced approach in his entomological studies, dealing with behavioral and taxonomic problems alike. He also became a self-conscious pioneer in the study of biogeography, observing that temperature alone is insufficient to explain animal distribution and calling attention to the way in which animal distribution is related to the distribution of food sources. Along other lines in the 1820’s he advanced theoretical views displaying sympathy with the concept of the unity of plan in the animal kingdom.
Among such strong personalities as Cuvier, Lamarck, Geoffroy Saint-Hilaire, and Blainville, Latreille was a modest, unassuming figure. Although his concerns, as suggested here, were by no means limited to questions of insect classification, he was inclined to leave to others the formulation of broad systems and philosophies. With étienne Geoffroy Saint-Hilaire he cosigned a report to the Institut that precipitated the famous Cuvier-geoffroy debate in 1830. The report, on a memoir in which Laurencet and Meyranx had proposed an analogy between the cephalopods and the vertebrates, was, however, written by Geoffroy alone. Latreille, according to a letter he wrote to Cuvier, wished no credit for it, asserting that he himself had given up the idea he had once entertained of considering the invertebrates and vertebrates as constructed upon the same plan.4
On another speculative front Latreille’s stand was less ambiguous. Although he was for many years Lamarck’s assistant and friend, he did not share his mentor’s evolutionary views. He found it impossible to conceive of the forms of insects, and in particular their instinctual behavior, as anything other than the evidence of divine wisdom and design. Furthermore, as he remarked on this view of creation shortly before he died: “If we are wrong, do not seek to destroy illusions which are useful rather than harmful to society and which make us happy or console us in the difficult pilgrimage of life.” 5
1. Louis de Nussac, Latreille à Brive, pp. 25-43, presents in detail the often-told story of how Latreille, imprisoned during the Revolution as a priest who had not preached a sermon, gained his release through the attention focused on him by his chance discovery in his cell of a previously unknown species of beetle.
2. J. P. F. Deleuze, Histoire et description du Muséum royal d’histoire naturelle (Paris, 1823), p. 188.
3. Émile Blanchard, Métamorphoses, moeurs et instincts des insectes (Paris, 1877), p. 33.
4. Institut de France, MS 3060 (1).
5. Latreille, Cours d’ entolologie, p. 21.
I. Original Works. Latreille’s publications total over seventy titles, excluding his contributions to various dictionaries of natural history. A reasonably accurate list of these appears in “Latreille,” in Nouvelle biographie générale (Paris, 1862), XXIX, 851-854. The entomological titles alone have been compiled by A. Percheron, Bibliographie entomologique (Paris, 1837), I, 228-235. Among Latreille’s more important works are Précis des caractère génériques des insectes disposés dans un ordre naturel (Brive, an v [1796[); Histoire naturelle, générale et particulière des crustacés et des insectes. Ouvrage faisant suite eux oeuvres de … Buffon, rédifé par C.S. Sonnini…, 14 vols. (Paris, 1802-1805); Genera crustaceorum et insectorum secundum ordinem naturalem in familias disposita, 4 vols. (Paris, 1806-1909); Les crustacés, les arachnides et les insectes, vol. III of Georges Cuvier, Le règne animal distribué d’ après son organisation, pour servir de base à l’histoire naturelle des animaux et d’introduction à l’ anatomie comparée (Paris, 1817)—also vols. IV and V of the 1829 ed.; and Cours d’entomologie, ou de l’histoire naturelle des crustacás, des arachnides, des myriapodes et des insectes (Paris, 1831).
The Société Entomologique de France has a collection of Latreille materials numbering 1,637 items, grouped in the following categories: (1) titles and distinctions; (2)MSS of various published scientific works; (3) unpublisched works; and (4) scientific correspondence withother entomologists.
II. Secondary Literature. There is no full treatment of Latreille’s life and scientific work. See Louis de Nussac, Pierre-André Latreille à Brive de 1762 à 1798 (Paris, 1907); and “Le centenaire de Pierre–André Latreille,” in Archives du Muséum national d’histoire naturelle, 6th ser., 11 (1934), 1-12; and A. J. L. Jourdan, “Latrille,” in Biographie universelle. Ancienne et moderne new ed. (paris, n.d.), XXIII, 329-331. For a discussion of Latreille’s classificatory contributions, see Henri Daudin, cuvier et Lamarck, les classes zoologiques et l’idée de série animale (1790-1830) (Paris, 1926).
Richard W. Burkhardt, Jr.