Text-book of structural and physiological botany . ey comeinto contact with the ovules and attach themselves closely tothem (Fig. 359). One of the cells of the nucleus of theovule has, in the meantime, grown much larger than therest, and has pressed aside and absorbed the surroundingtissue. This is the embryo-sac, in which, even before fer-tilisation, two membraneless cells, the embryonic or germinalvesicles,^ have been formed, which are fertiHsed by the pollen- ^ More than two embryonic vesicles sometimes occur, thoughnormally in only a few plants, as Citrus. 188 SUntctural and Physiological
Text-book of structural and physiological botany . ey comeinto contact with the ovules and attach themselves closely tothem (Fig. 359). One of the cells of the nucleus of theovule has, in the meantime, grown much larger than therest, and has pressed aside and absorbed the surroundingtissue. This is the embryo-sac, in which, even before fer-tilisation, two membraneless cells, the embryonic or germinalvesicles,^ have been formed, which are fertiHsed by the pollen- ^ More than two embryonic vesicles sometimes occur, thoughnormally in only a few plants, as Citrus. 188 SUntctural and Physiological Botany, tube, and then develope into the embryo. Besides the em-bryoniS vesicles, the embryo-sac usually contains one ormore cells, the functionof which is still un-known, and which arecalled the antipodal cells(Fig. 360), because theyare usually found at thebase of the the numerouspollen-tubes which, as arule, reach the ovule,one penetrates throughthe micropyle, andreaches the embryo-saceither directly or byforcing aside the tissue. Fig. 360 —Upper part of thenucleus of the ovule ofCroats ; p the embryo-sacwith its nucleus zk; kthe embryonic vesicles;^ the antipodal cells, (x75.)
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