This collection of Jean-Baptiste Lamarck's lectures provides a wealth of information about the man and his theories. Arguing that Lamarck's ideas about evolution, initially discredited, are increasingly shown to have been prescient and important, this study contends that though many of Lamarck's insights may have been flawed, his basic contention that environment and evolution are inexorably linked is invaluable, particularly in the era of the genome project. At a time when Lamarckian notions of a vital universe are replacing mechanistic views, this work provides an excellent summation of his ideas and of their increased importance.