. Plant life, considered with special references to form and function. Plant physiology. F£J^.yil'OA'yS AND SEKD-PLAiXrs. 6i of nutrition lias been sliifted from the ganieto]ih\ te l(j the sporophyte; anci this e\'en when tlie gametophyte has its largest size and greatest duration, while nutritive work is wholly abandoned in the smaller forms. The sporo|)hyte has also become the long-lived stage, the gametophvte being usually transitorv (only exceptionally living more than one season), while the sporophyte lives through one season in the few annuals, and commonly for several or e\en man\- yea
. Plant life, considered with special references to form and function. Plant physiology. F£J^.yil'OA'yS AND SEKD-PLAiXrs. 6i of nutrition lias been sliifted from the ganieto]ih\ te l(j the sporophyte; anci this e\'en when tlie gametophyte has its largest size and greatest duration, while nutritive work is wholly abandoned in the smaller forms. The sporo|)hyte has also become the long-lived stage, the gametophvte being usually transitorv (only exceptionally living more than one season), while the sporophyte lives through one season in the few annuals, and commonly for several or e\en man\- years. 72. The embryo.âThe fertilized egg, from which the sporophyte arises, develops while still embedded in the gametoph\'te in which it is formed. Consequently the embryo sporophyte is, as in the mossworts, at first surrounded by the gametophyte (figs. 76, 77). The part of the gamet- ophyte adjacent to the embryo grows under the stimulus of its presence, but the growth of the embryo is more rapid, and it consequently spreads apart the gametophyte (see figs. 76, 77). A portion of the embryo de- velops a temporary organ, the foot, which remains euibedded in the gametophyte until the first root, stem, and leaf have been formed (fig. 7S). Soon thereafter the gametophyte per- ishes and the foot, no longer ^ , J. Fig. 78.âThe same as fig. 77, older. USelul, disappears. The gametophyte. /, seen from be- ^n .«*. 1 '-1^1 , low. with rhizoids; the sporophyte 73. Members. Ihe mature stlll attached but with primary leaf", /, , . J ⢠r,- ,.- t J â t developed into blade and stalk ;/. the sporophyte is dltlerentiated into primary root: _=, a secondary root, J , fpi arising from the juncture of leaf-stalk root. Stem, and leaves. 1 ne and stem. .Magnified about 4 diam,â 1 , ,.â c ^-L .After Sachs. important adaptations ot the structure and forms of these members are so similar to those. Please note that these images are extracted from scanned page images that may have been di
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Keywords: ., book, bookcentury1800, bookdecade1890, booksubjectplantphysiology
