Petunia violacea, crossed and self-fertilised plants compared for four generations. Effects of a cross with a fresh stock. Uniform colour of the flowers on the self-fertilised plants of the fourth generation. Nicotiana tabacum, crossed and self-fertilised plants of equal height. Great effects of a cross with a distinct sub-variety on the height, but not on the fertility, of the offspring. Cyclamen persicum, crossed seedlings greatly superior to the self-fertilised. Anagallis collina. Primula veris. Equal-styled variety of Primula veris, fertility of, greatly increased by a cross with a fresh stock. Fagopyrum esculentum. Beta vulgaris. Canna warscewiczi, crossed and self-fertilised plants of equal height. Zea mays.