Elementary biology; an introduction to Elementary biology; an introduction to the science of life elementarybiolog00grue Year: 1924 ALTERNATION OF GENERATIONS 321 When the moss is covered over with water, it is possible for the male gametes to swim about, and. some of them find their way into the archegonium. Here one of the sperm cells fuses with the egg cell, and the fertilized egg cell begins to develop into a new moss plant immediately — that is, while still within the body of the parent. Fig. 149. Alternation of generations in the life history of the moss G, the gametophyte, or gamete
Elementary biology; an introduction to Elementary biology; an introduction to the science of life elementarybiolog00grue Year: 1924 ALTERNATION OF GENERATIONS 321 When the moss is covered over with water, it is possible for the male gametes to swim about, and. some of them find their way into the archegonium. Here one of the sperm cells fuses with the egg cell, and the fertilized egg cell begins to develop into a new moss plant immediately — that is, while still within the body of the parent. Fig. 149. Alternation of generations in the life history of the moss G, the gametophyte, or gamete-bearing plant; /, the female gamete organ; ;«, the male gamete organ; c. the fertilized egg resulting from the fusion of egg and sperm; S, the sporophyte. or spore-bearing plant; s, spores. The spore always develops into a gameto- phyte ; the gametes (egg) always give rise to a sporophyte. G and S represent alternate generations that reproduce in different ways,— the first sexually, by means of gametes, the second asexually, by means of spores But the new plant is very different from the parent plants. It has no leaflike organs or anything to correspond to leaves. It consists mainly of stalk, and at its base it is buried in the tissues of the parent plant, from which it gets most of its nourishment. It is therefore parasitic upon the parent to a large extent. At the end of the stalk a capsule is formed, and when this is ripe, a great many sJ>ores are
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