1893. August Weismann publishes The Germ Plasm. His germ plasm theory states that inheritance only takes place through germ cells (gametes, such as egg or sperm cells) and not through the somatic cells (the cells forming organs, bones or other tissue) that carry out an organism's functions. This theory refuted the Lamarckian concept that organisms can pass down characteristics acquired during their lifetime to their offspring and offered support to Darwin's theories of evolution. It is considered one of the scientific origins of eugenic thought.

This theory was successful in convincing a majority of scientists, and was therefore highly influential. Weisman's theory was also used by degeneracy theorists to support negative eugenics (Carlson, n.d.).

This book may be read online.

-Amy Dyrbye

• Carlson, E. (n.d.). Scientific Origins of Eugenics. Image Archive on the American Eugenics Movement. Retrieved from http://www.eugenicsarchive.org/html/eugenics/essay2text.html.