Note 152 — A DEFENCE OF MENDEL’S PRINCIPLES OF HEREDITY. (continued 2)

In his latest publication on this subject, the notes to the edition of Mendel in Ostwald’s Klassiker (pp. 60–61), Tschermak, who has seen more true exceptions than any other observer, thus refers to them. As to dominance:—“Immerhin kommen vereinzelt auch zweifellose Fälle von Merkmalmischung, d. h. Uebergangsformen zwischen gelber und grüner Farbe, runder und runzeliger Form vor, die sich in weiteren Generationen wie dominantmerkmalige Mischlinge verhalten.” As to purity of the extracted recessives:—Ganz vereinzelt scheinen Ausnahmsfälle vorzukommen."

Küster (22) also in a recent note on Mendelism points out, with reason, that the number of “exceptions” to dominance that we shall find, depends simply on the stringency with which the supposed “law” is drawn. The same writer remarks further that Mendel makes no such rigid definition of dominance as his followers have done.