. A handbook of cryptogamic botany. Cryptogams. FUCACEM 233 are a prolongation of those of which the thallus is composed, and frequently project, through the mouth or ostiole of the conceptacle, into the surrounding water. When infertile these hyphse are known as paranemes or paraphyses. In the male conceptacles they are usually branched, unbranched in the female. Both the barren and fertile con- ceptacles are always first formed in the neighbourhood of the growing point, the cavity originating from the absorption of a row of cells at right angles to the surface. The antherids are produced on
. A handbook of cryptogamic botany. Cryptogams. FUCACEM 233 are a prolongation of those of which the thallus is composed, and frequently project, through the mouth or ostiole of the conceptacle, into the surrounding water. When infertile these hyphse are known as paranemes or paraphyses. In the male conceptacles they are usually branched, unbranched in the female. Both the barren and fertile con- ceptacles are always first formed in the neighbourhood of the growing point, the cavity originating from the absorption of a row of cells at right angles to the surface. The antherids are produced on lateral branches of the hyphse in the male or in the upper part of bisexual conceptacles. Each consists of an ovoid thin-walled or sometimes double-walled cell, the abundant protoplasm of which breaks up into a number (usually sixty-four) of. Fig. 209.—Section of female conceptacle of F. vesicitlosiis^ clothed with unbranched hyphffi bearing the oogones ; c, ostiole (magnified). minute antherozoids, pointed at one end, with a pair of cilia of unequal length placed laterally below the beak-like apex, and contains an orange- red pigment spot and a nucleus. The olive-brown oogones are developed from unbranched hyph» in the female, or in the lower part of bisexual conceptacles. These fertile hyphae are at fii-st unicellular, and are bounded at the base by a septum ; the single cell subsequently divides into a basal pedicel-cell, and an upper portion, which swells into a spherical or ellipsoidal form, the oogone, filled with protoplasm coloured brown by phycophsein, and always provided with a wall composed of two layers. Either the whole of the contents of the oogone contract into a single oosphere, or it divides into two, four, or eight oospheres, each with its own nucleus. Impregnation always takes place outside. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustr
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