The name shared by Charles Darwin's grandfather and brother, each important in his life and work. Charles's grandfather Erasmus (1731-1802) was a glorious polymath-physician-author, and botanist. His impact is reflected throughout a wide range of disciplines from the poetry to the technology of his day. Author of The Loves of the Plants, a 2.000-line poem detailing their sexual reproduction, and Zoonomia, or the Theory of Generations, whose themes echo throughout his grandson's work. Charles's older brother Erasmus (1805-1881), known as "Ras," used his network of social and scientific contacts to advance the theories of his shyer, more retiring sibling.