Adolphe Théodore Brongniart (1801-1876), French botanist, son of the geologist Alexandre Brongniart, was born in Paris on the 14th of January 1801. He soon showed an inclination towards the study of natural science, devoting himself at first more particularly to geology, and later to botany, thus equipping himself for what was to be the main occupation of his life - the investigation of fossil plants. In 1826 he graduated as doctor of medicine with a dissertation on the Rhamnaceae; but the career which he adopted was botanical, not medical. In 1831 he became assistant to R.L. Desfontaines at the Musée d'Histoire Naturelle, and two years later succeeded him as professor, a position which he continued to hold until his death in Paris on the 18th of February 1876.
Brongniart was an indefatigable investigator and a prolific writer, so that he left behind him, as the fruit of his labours, a large number of books and memoirs. As early as 1822 he published a paper on the classification and distribution of fossil plants (Mém. Mus. Hist. Nat. viii.). This was followed by several papers chiefly bearing upon the relation between extinct and existing forms - a line of research which culminated in the publication of the Histoire des végétaux fossiles, which has earned for him the title of "father of palaeobotany." This great work was heralded by a small but most important "Prodrome" (contributed to the Grand Dictionnaire d'Hist. Nat., 1828, t. lvii.) which brought order into chaos by a classification in which the fossil plants were arranged, with remarkably correct insight, along with their nearest living allies, and which forms the basis of all subsequent progress in this direction. It is of especial botanical interest, because, in accordance with Robert Brown's discoveries, the Cycadeae and Coniferae were placed in the new group Phanérogames gymnospermes.
In this book attention was also directed to the succession of forms in the various geological periods, with the important result (stated in modern terms) that in the Palaeozoic period the Pteridophyta are found to predominate; in the Mesozoic, the Gymnosperms; in the Cainozoic, the Angiosperms, a result subsequently more fully stated in his "Tableau des genres de végétaux fossiles" (D'Orbigny, Dict. Univ. d'Hist. Nat., 1849). But the great Histoire itself was not destined to be more than a colossal fragment; the publication of successive parts proceeded regularly from 1828 to 1837, when the first volume was completed, but after that only three parts of the second volume appeared. Brongniart, no doubt, was overwhelmed with the continually increasing magnitude of the task that he had undertaken. Apart from his more comprehensive works, his most important palaeontological contributions are perhaps his observations on the structure of Sigillaria (Arch. Mus. Hist. Nat. i., 1839) and his researches (almost the last he undertook) on fossil seeds, of which a full account was published posthumously in 1880. His activity was by no means confined to palaeobotany, but extended into all branches of botany, more particularly anatomy and phanerogamic taxonomy.
Among his achievements in these directions the most notable is the memoir "Sur la génération et le développement de l'embryon des Phanérogames" (Ann. Sci. Nat. xii., 1827). This is remarkable in that it contains the first account of any value of the development of the pollen; as also a description of the structure of the pollen-grain, the confirmation of G. B. Amici's (1823) discovery of the pollen-tube, the confirmation of R. Brown's views as to the structure of the unimpregnated ovule (with the introduction of the term "sac embryonnaire"); and in that it shows how nearly Brongniart anticipated Amici's subsequent (1846) discovery of the entrance of the pollen-tube into the micropyle, fertilizing the female cell which then develops into the embryo. Of his anatomical works, those of the greatest value are probably the "Recherches sur la structure et les fonctions des feuilles" (Ann. Sci. Nat. xxi., 1830), and the "Nouvelles Recherches sur l'épiderme" (Ann. Sci. Nat. i., 1834), in which, among other important observations, the discovery of the cuticle is recorded; and, further, the "Recherches sur l'organisation des tiges des Cycadées" (Ann. Sci. Nat. xvi., 1829), giving the results of the first investigation of the anatomy of those plants.
His systematic work is represented by a large number of papers and monographs, many of which relate to the flora of New Caledonia; and by his énumération des genres de plantes cultivées au Musée d'Histoire Naturelle de Paris (1843), which is an interesting landmark in the history of classification in that it forms the starting-point of the system, modified successively by A. Braun, A.W. Eichler and A. Engler, which is now adopted in Germany. In addition to his scientific and professorial labours, Brongniart held various important official posts in connexion with the department of education, and interested himself greatly in agricultural and horticultural matters. With J.V. Audouin and J.B.A. Dumas, his future brothers-in-law, he established the Annales des Sciences Naturelles in 1824; he also founded the Société Botanique de France in 1854, and was its first president.
For accounts of his life and work see Bull. de la Soc. Géol. de France, 1876, and La Nature, 1876; the Bulletin de la Soc. Bot. de France for 1876, vol. xxiii., contains a list of his works and the orations pronounced at his funeral.
(S. H. V.*)