188

PETUNIA YIOLACEA.

Chap. VI.

CHAPTER VI.

SOLANACE-E, PRIMULACE.E, PoLYGONE.E, ETC.

I’etuuia violaoea, crossed and self-fertilised plants compared for fourgenerations—Effects of a cross with a fresh stock—Uniform colourof the flowers on the self-fertilised plants of the fourth generation—Nicotiana tabaeum, crossed and self-fertilised plants of equalheight—Great effects of a cross with a distinct sub-variety on theheight, but not on tho fertility, of the offspring—Cyclamen per-sieuin, crossed seedlings greatly superior to the self-fertilised—Anagallis collina—Primula veris—Equnl-styled variety of Primulaveris, fertility of, greatly increased by a cross with a fresh stock—Fagupyrum esculentum—Beta vulgaris—Oanna warscewiczi, crossedand self-fertilised plants of equal height—Zea mays —Phalariscanariensis.

XXV. SOLANACE2E.— Petunia violacea.

Dingy purple variety.

The flowers of this plant are so seldom visited during the dayby insects in this country, that I have never seen an instance;but my gardener, on whom I can rely, once saw some humble-bees at work. Mr. Meehan says,* that in the United States bees bore through the corolla for the nectar, and adds that their“ fertilisation is carried on by night-moths.”

In France M. Naudin, after castrating a large number of flowerswhilst in bud, left them exposed to the visits of insects, andabout a quarter produced capsules ;f but I am convinced thata much larger proportion of flowers in my garden are cross-fertilised by insects, for protected flowers with their own pollenplaced on the stigma never yielded nearly a full complement ofseed; whilst those left uncovered produced fine capsules, showingthat pollen from other plants must have been brought to them,probably by moths. Plants growing vigorously and flowering inpots in the grecn-liouse, never yielded a single capsule; and

* ‘ Proc. Acad. Nat. Sc. of Phil- t ‘Annales des Sc. Nat.’ 4thadelphia,’ Aug. 2nd, 1870, p. 90. aeries, Bot. tom. ix. cah. 5.