These lectures, numbered 1 through 39 and three unnumbered, were delivered at Mr. Peale's Museum and are on such topics as natural history, physical phenomena and the elements, quadrupeds, fishes, birds, primates, and systems of identification. There are notes in the lectures for pauses, music, and illustrations to be included.

This collection contains color slides of drawings and watercolors on vellum made by Lesueur in 1799, when he accompanied Baudin and Francois Péron on their scientific expedition to Australia. The microfilm is of Lesueur's American sketchbooks.

This collection contains correspondence on natural history, expecially mollusks, fishes, and birds, and on medicine and social affairs, with references to the British Museum of Natural History. Also included are a paper by Owen on dinosaurs and a synopsis of a course of lectures, 1857.