. Morphology of angiosperms (Morphology of spermatophytes. Part II). Angiosperms; Plant morphology. 98 MORPHOLOGY OP ANGIOSPERMS In other instances the activity of the antipodal cells is v their great increase in size and usually multinucleate shown condition, and also by their more or less extensive division. Among the Monocotyledons, the Sparganiaceae, Gramineae, and Araceae are conspicuous for their strongly developed antip- odal cells. In Sparganium simplex Campbell63 describes the. Fig. 45.—Sparganium simplex. Lower end of embryo-sac showing- a large mass of antipodal cells.—After Cam
. Morphology of angiosperms (Morphology of spermatophytes. Part II). Angiosperms; Plant morphology. 98 MORPHOLOGY OP ANGIOSPERMS In other instances the activity of the antipodal cells is v their great increase in size and usually multinucleate shown condition, and also by their more or less extensive division. Among the Monocotyledons, the Sparganiaceae, Gramineae, and Araceae are conspicuous for their strongly developed antip- odal cells. In Sparganium simplex Campbell63 describes the. Fig. 45.—Sparganium simplex. Lower end of embryo-sac showing- a large mass of antipodal cells.—After antipodal cells as at first very small, but immediately after fertilization they enlarge to several times their original size, their nuclei dividing. Finally, a conspicuous hemispherical mass of 100 to 150 uninucleate cells is formed, at this stage the endosperm having hardly at all developed (Fig. 45). The strong development of antipodal cells among the Gramineae has long been known, Fischer 8 having reported in 1880 that each antipodal cell of Ehrarta panicea divides once, and of Alopecurus pratensis three or more times. More recently Cannon80 found in Arena fatua that the antipodal cells lie- come thirty-six or more in number before fertilization, and begin to disorganize with the beginning of endosperm devel- opment. Westermaier 2S has described a growth of antipodal tissue in Zen and other grasses before fertilization, and Guignard 00 has found as many as twelve multinucleate cells in the much, narrowed antipodal end of the embryo-sac of Zea. It is of interest to note in this connection that in 1882 the same investigator12 found in Cornucopiae undivided but prominent and often binucleate antipodal cells. Among the Araceae Campbell 75 states that there is a general tendency for tin.' antipodals to develop strongly, often dividing and forming a tissue, and in Lysichiton kamtschatcense the same observer63 finds that at the time of fertilization the antipodal nucl
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