Public Domain Mark
You can use this work for any purpose without restriction under copyright law. Read more about this licence.
Credit
Diagram of the composition of the germ-plasm in hybrids, fig. 22 in chapter 'The Phenomena of Reversion', p. 303 The Germ-Plasm: A Theory of Heredity by August Weismann, London, Walter Scott, 1893. Wellcome Collection. Public Domain Mark. Source: Wellcome Collection.