. A handbook of cryptogamic botany. Cryptogams. CHARACE.'E S79 The Characese are either monoecious 9r dicEcious, In the former case the male and female organs are formed in close juxtaposition on the same node, the archegone being somewhat below the antherid in Nitella, above it or by its side in Chara. The archegones, like the antherids, are metamorphosed leaves. When ready for fertilisation, the archegone has a, longer or shorter ovoid form, and is borne on a short pedicel-cell. In the interior is an axial row of cells enveloped by five tubes, which are at first straight, but are afterwards
. A handbook of cryptogamic botany. Cryptogams. CHARACE.'E S79 The Characese are either monoecious 9r dicEcious, In the former case the male and female organs are formed in close juxtaposition on the same node, the archegone being somewhat below the antherid in Nitella, above it or by its side in Chara. The archegones, like the antherids, are metamorphosed leaves. When ready for fertilisation, the archegone has a, longer or shorter ovoid form, and is borne on a short pedicel-cell. In the interior is an axial row of cells enveloped by five tubes, which are at first straight, but are afterwards coiled spirally round the axial row. The lowest portion of each of these tubes is an elongated unsegmented â cell; while at the upper part â one or two very small cells are segmented off. In Nitella each of the terminal cells again di- vides into two by a vertical septum. The five terminal cells of Chara and the ten terminal cells of Nitella are not twisted, and form together the crown. When the archegone is ready for impregnation these crown- cells separate from one another, forming the neck, and leaving an open passage down to the axial row. This apical cavity is, how- ever, very nearly closed below iby a diaphragm formed by the projecting inwards of the five Tieck-cells, through which there is only a very narrow opening for the entrance of the anther- ozoids. The apical cell of the axial row is much larger than the rest, and is the female or ^erm-cell, corresponding to the central cell in the archegone of the higher Cryptogams. It is filled with protoplasm, oil-drops, and starch-grains; its apical portion, the apical papilla, or receptive spot, containing only hyahne protoplasm. Between the apical cell and the pedicel-cell of the archegone, there is in Chara only a single cell, in Nitella a group of cells, the ' Wendungszellen.' Before fertilisation the â¢crown is a compact structure covering the apical cavity ; but when the .archegone is ready for impregnation a small a
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