Text-book of structural and physiological botany . lY. /^^ IIL. Fig. 449.—Marsilea salvatrix ; I. a macrcspore before fertilisation with its mucila-ginous envelope.; the pro-embr^^o is developed from the roundish papilla p at theapex of the spherical spore (x 15); (5 microspores (x 15), c single microspore(x 100) ; n. antherozoid with its attached vesicle (x 690); III. pro-embryo withoospore seen in transverse section ; the spherical oospore o has already a cell-wall(x 200); IV. young plant seven days later still attached to the spore/(x 7)(all after JIanstein). which immediately surround the
Text-book of structural and physiological botany . lY. /^^ IIL. Fig. 449.—Marsilea salvatrix ; I. a macrcspore before fertilisation with its mucila-ginous envelope.; the pro-embr^^o is developed from the roundish papilla p at theapex of the spherical spore (x 15); (5 microspores (x 15), c single microspore(x 100) ; n. antherozoid with its attached vesicle (x 690); III. pro-embryo withoospore seen in transverse section ; the spherical oospore o has already a cell-wall(x 200); IV. young plant seven days later still attached to the spore/(x 7)(all after JIanstein). which immediately surround the central cell, and whichtherefore constitute the archegonium. At the proper timeone or more antherozoids force themselves through the neckof this archegonium, and presumably disappear in the in-terior of the central cell, in an oosphere. The oosporeor fertilised oosphere then becomes surrounded by a cell-wall (Fig. 449 III., <?), divides into new cells, and graduallygrows into a new plant (Fig. 449 iv.). In their alternation special Morphology and Cl
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Keywords: ., bookcentury1800, bookdecade1870, bookpublishernewyorkjwileysons
