basis, which was a great stride upon the work of his predecessors. Lamarck arranged the various groups of animals in linear order from lower to higher—a scala naturæ; Cuvier opposed this system, and established the idea of diverging branches (embranchements), although, unlike Lamarck, he was no evolutionist.
While at the Normandy town, with its beautiful cathedral of St Pierre, Cuvier made the acquaintance of the old Abbé Tessier, then hiding from the fury of Robespierre and other revolutionists. Disguised as a surgeon, the learned old man discovered the worth of young Cuvier, and this introduction was the means of putting the latter into communication with Jussieu, Geoffroy Saint-Hilaire, Daubenton, Lapécède, and other men of science.
In 1795 Cuvier was appointed an assistant to the professor of anatomy in the Musée d'Histoire Naturelle. The same year saw him established as professor at the École Centrale du Panthéon—and here he composed his Tableau élémentaire de l'Histoire Naturelle des Animaux—the basis of the modern system of classification of the animal kingdom. At this time Mertrud, aided by the brothers Cuvier, commenced the famous and extensive collection of comparative anatomy at the Jardin des Plantes, Paris; and the next year Cuvier was elected a member of the Académie des Sciences.
In 1796 he discovered red blood in leeches (Hirudo),
