Variation of colour in rats as described in Mendel's Law, plate 6 in Genetics and Eugenics by W. E. Castle, Harvard University Press, 1916
Licence: In copyright
Credit: Variation of colour in rats as described in Mendel's Law, plate 6 in Genetics and Eugenics by W. E. Castle, Harvard University Press, 1916. Wellcome Collection. Source: Wellcome Collection.