She is called "_Mademoiselle_," though she was married. The name of "_dame_" was in her time still restricted to women of noble birth. And she remains "Mademoiselle;" is never cited except under her maiden name. Her books, from their pure science and great perseverance, give one the idea of a person lifted above the world of persons, and wholly devoted to art and nature. I have dedicated to her a word or two, but without speaking of her life. A native of Bâle, the daughter, sister, and mother of celebrated engravers, and herself an excellent painter of flowers upon velvet, she long resided at Frankfort and Nurenberg. She experienced great misfortunes, her husband being ruined and having separated from her. She then sought refuge in a mystical society, analogous to that which had formerly consoled Swammerdam. The religious spark of the new science, _the theology of insects_, as a contemporary terms it, here produced a strong impression on her mind. She was acquainted with Swammerdam's great idea, the unity of metamorphoses, and with that which Malpighi had flung in the face of astonished Europe in his book on the silkworm: "Insects have a heart." What! they have a heart, like us! Which, like ours, throbs and stirs at the impulse of their desires, their fears, or their passions! How touching an idea! How well adapted to influence a woman!--But is this a fact? Many long denied it, but doubt has been impossible since the truth was demonstrated in 1824 in M. Strauss's treatise on "The Cockchafer." Madame de Mérian, then, started from the silkworm. But her curiosity and artistic eagerness embraced everything. Contrasted with her dull and sombre Germany, Holland, with its rich American and Oriental collections, appeared to her like the great museum of the tropics. There she established herself, and with her pencil made its collections her own. Those faëry cemeteries, glittering with the beauty of the dead, did but whet in her the desire to investigate life in the region where it most luxuriates. At the age of fifty-four she set out for Guiana; and, during a two years' residence in its dangerous climate, collected the drawings and paintings which were to inaugurate art in natural history.