The structure & development of the mosses and ferns (Archegoniatae) . Fig. 45.—Porella Bolanderi (Aust.)- A, B, Cross-sections of young antheridia, x6oo; C, longi-tudinal section of nearly ripe antheridium, X loo; D, ripe antheridium in the act of opening,X50; E, F, spermatozoids, X 1200. antheridium look almost pure white. If one of these is broughtinto water it soon opens in a very characteristic way. Thecells of the wall absorb water with great avidity, and finallythe upper part bursts open by a number of irregular lobeswhich curl back so strongly that many of the marginal cellsbecome compl
The structure & development of the mosses and ferns (Archegoniatae) . Fig. 45.—Porella Bolanderi (Aust.)- A, B, Cross-sections of young antheridia, x6oo; C, longi-tudinal section of nearly ripe antheridium, X loo; D, ripe antheridium in the act of opening,X50; E, F, spermatozoids, X 1200. antheridium look almost pure white. If one of these is broughtinto water it soon opens in a very characteristic way. Thecells of the wall absorb water with great avidity, and finallythe upper part bursts open by a number of irregular lobeswhich curl back so strongly that many of the marginal cellsbecome completely detached. The whole mass of sperm cells,with the included spermatozoids, is forced out into the water,and if they are perfectly mature, the spermatozoids are quicklyliberated and swim away (Fig. 45, D). The female plants are decidedly larger than the males, but I02 MOSSES AND FERNS .chap. the archegonial branches are much less conspicuous than theantheridial ones. The older ones, which either contain a youngsporogonium or abortive archegonia, are readily di
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Keywords: ., bookcentury1800, bookdecade1890, bookidstructuredev, bookyear1895
