CHAPTER VI.

SOLANACEAE, PRIMULACEAE, POLYGONEAE, ETC.

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.--Phalaris canariensis.