. Plant life, considered with special references to form and function. Plant physiology. SEXUAL REPRODUCTION. 291 is much simplified, the neck-cells and the egg being the only distinct parts of maturity. 393. Gymnosperms.—In the gymnosperms the female gametophyte is not large enough to burst the megaspore which. spm, Fig. 333.—Longitudinal section of the female gametopliyte of Selaginella Martensii. (/, ^, ^, the body of gametophyte; r, ?-, rhizoids (rudimentary) on its surface; a, an ovary whose egg failed of fertilization ; e, embryo de\'eloped from fertilized egg; its cell-structure is not
. Plant life, considered with special references to form and function. Plant physiology. SEXUAL REPRODUCTION. 291 is much simplified, the neck-cells and the egg being the only distinct parts of maturity. 393. Gymnosperms.—In the gymnosperms the female gametophyte is not large enough to burst the megaspore which. spm, Fig. 333.—Longitudinal section of the female gametopliyte of Selaginella Martensii. (/, ^, ^, the body of gametophyte; r, ?-, rhizoids (rudimentary) on its surface; a, an ovary whose egg failed of fertilization ; e, embryo de\'eloped from fertilized egg; its cell-structure is not shown, but the \'arious members are begun ; .(, suspensor ; st. stem; /. /, primary lea\-es ; rt, root; /, foot; e', a younger embryo, with cell-structure shown, tlie letter standing in large suspensor cell; i-/?jz, wall of megaspore. Magnified 125 diam, —After Pfel^er. remains enclosed in the sporangium. Upon its surface are formed several ovaries, each reduced to an egg and two to four tiers of neck-cells (figs. 320, 321). 394. Angiosperms.—In the angiosperms the female gam- etophyte is so simplified that it is represented only by a few cells, among which may be recognized at least one egg (e, fig. 334), and possibly two others, s, s. The ovary has been reduced to nothing but an egg, and the full development of the gametophyte seems to be delayed until after the egg is. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Barnes, Charles Reid, 1858-1910. New York, H. Holt & company
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