Note 50 — Chapter III

The now famous Mendelian Law of Inheritance, first discovered in 1865 by Mendel, an Augustinian monk and Abbott of Brünn, and completely ignored till the year 1900, when it was rediscovered by De Vries and others, is also strongly confirmatory of Weismann’s analysis of the principle of heredity. According to this law it is possible, as it were, to isolate any particular characteristic of a species or even (if heritable) of an individual, and by a definite system of crossing to attach this characteristic alone to any other variety capable of crossing with the first. This means that inheritance is governed by separable units of formative energy. These units are Weismann’s determinants. The discovery of the methods of turning this principle to practical account is obviously of great importance for agriculture and stockbreeding. The law has some inexplicable limitations which are now closely engaging the attention of biologists. It is impossible to enter upon the subject more fully here, but a good account of it will be found in Lock’s Recent Progress in the Study of Variation, and in a brochure, An Address on Mendelian Heredity, by W. Bateson, reprinted from Brain, pt. cxiv, 1906.