August Friedrich Leopold Weismann FRS (For), HonFRSE, LLD was a German evolutionary biologist. Fellow German Ernst Mayr ranked him as the second most notable evolutionary theorist of the 19th century, after Charles Darwin. Weismann became the Director of the Zoological Institute and the first Professor of Zoology at Freiburg.
August Weismann
Aufsätze über Vererbung und verwandte biologische Fragen, 1892
Germ plasm is a biological concept developed in the 19th century by the German biologist August Weismann. It states that heritable information is transmitted only by germ cells in the gonads, not by somatic cells. The related idea that information cannot pass from somatic cells to the germ line, contrary to Lamarckism, is called the Weismann barrier. To some extent this theory anticipated the development of modern genetics.
August Weismann proposed the germ plasm theory in the 19th century, before the foundation of modern genetics.