Elementary botany . 326 MORPHOLOG Y. of pear fruit, the latter being kept in a moist chamber to prevent dryingthe surface. 652. In the spring after flowering the pollen escapes from the anther sacs,and as a result of pollination is brought to rest on the stigma of the it germinates, as we say, that is, it develops a long tube which makesits way down through thestyle, and in through themicropyle to the embryo sac,where, in accordance withwhat takes place in otherplants examined, one of thesperm cells unites with theegg, and fertilization of theegg is the result. 653. Macrospore and
Elementary botany . 326 MORPHOLOG Y. of pear fruit, the latter being kept in a moist chamber to prevent dryingthe surface. 652. In the spring after flowering the pollen escapes from the anther sacs,and as a result of pollination is brought to rest on the stigma of the it germinates, as we say, that is, it develops a long tube which makesits way down through thestyle, and in through themicropyle to the embryo sac,where, in accordance withwhat takes place in otherplants examined, one of thesperm cells unites with theegg, and fertilization of theegg is the result. 653. Macrospore and embryo sac. three carpels are united into one,two carpels are also united into oneSimple pistils are found in manyin the ranunculaceae, the buttercups,These simple pistils bear a greater. -In trillium theand in dentaria thecompound pistil,plants, for examplecolumbine, to aleaf, the margins ofwhich are foldedaround so that theymeet and enclosethe ovules or spo-rangia. 654. If we cutacross the com-pound pistil of tril-lium we find thatthe infoldings of thethree pistils meet toform three partialpartitions whichextend nearly to the center, dividing off three spaces. In thesespaces are the ovules which are attached to the infolded we make cross sections of a pistil of the May-apple (podo-
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Keywords: ., bookauthoratk, bookcentury1900, bookdecade1900, booksubjectbotany
