At the Scottish Plant Breeding Station, a schelu2 for the breeding of potatoes, Solarium tuberuum L. with a view tc the production of new varieties of economic value is in operation. This paper consists of observations upon a number of pro- blems undertaken by the writer, who has been Assis- tant in charge of potato breeding work since 1926. Cultivated varieties of S. tuberosum L. both named and unnamed have been employed in connection with the major investigations and several wild species of tuber-bearing Solanaceae have been introduced in other experiments.

The experimentation to be discussed has been made for genetical study and for agricultural application. The observations related firstly to the mode of inheritance of characters affecting breeding work, namely flowering tendency and self sterility; and, secondly to the mode of inheritance of characters of agricultural importance, namely tuber skin colour, tuber shape and resistance to wart disease (S nch trium endobioticum Schilb.)