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ation of the law: Tallness being due to a factor T, a tall plant, arising by the union in fertilization of two germ cells both bearing this factor, is TT; a dwarf, being without T, is tt. Crossing these, crossbreeds, Tt, result (called generation F1). In the formation of the germ cells of these crossbreeds a process of…

f amoeboid cells flow together into a single mass) from which conjugation proper and even fertilization may have been evolved. -- Multiple fruits. (Bot.) See Collective fruit, under Collective. -- Multiple star (Astron.), several stars in close proximity, which appear to form a single system.

A special kind of spore resulting from the fertilization of an oösphere by antherozoids.

Direct fertilization in plants, as when the pollen fertilizing the ovules comes from the stamens of the same blossom; -- opposed to heterogamy.

power of developing without the intervention of the male element; the production, without fertilization, of cells capable of germination. It is one of the phenomena of alternate generation. Cf. Heterogamy, and Metagenesis.

The production of two or more embryos in one seed, due either to the existence and fertilization of more than one embryonic sac or to the origination of embryos outside of the embryonic sac.

The series of cells formed in the ovule of a flowering plant after fertilization, but before the formation of the embryo.

other animals, and by the larvæ of certain insects. It is capable of development without fertilization. See Illust. of Pædogenesis.

he gametophyte; and by the development of seeds. All the Spermatophyta are heterosporous; fertilization of the egg cell is either through a pollen tube emitted by the microspore or (in a few gymnosperms) by spermatozoids. The phrase "flowering plants" is less distinctive than "seed plants," since the conifers, grasses,…

The male germ cell in animals and plants, the essential element in fertilization; a microscopic animalcule-like particle, usually provided with one or more cilia by which it is capable of active motion. In animals, the familiar type is that of a small, more or less ovoid head, with a delicate threadlike cilium, or tail…

Fertilization of two ova, at the same menstruation, by two different acts of coition.

To let the tide or other water in upon (lowlying land), for the purpose of fertilization, by a deposit of warp, or slimy substance. [Prov. Eng.]

Cross fertilization.