. A handbook of cryptogamic botany. Cryptogams. FlG. I.—I., male catkin of Zamia (Cycadeae). II. III., antheriferous scale and pollen-sacs. FlG.^ 2.—Peltate scale of Eguisehtm^ with sporanges sg, (After Sachs.) sponding to the antherozoids, the pollen-grain itself becomes homologous with the microspore, the pollen-sac or anther-cell to the microsporange. Even in external appearance the pollen-sacs of Coniferse and Cycadeae bear a striking resemblance to the sporanges of some Vascular Crypto- gams. The modes of formation of the pollen-grains within the pollen- sac and of spores within the spora
. A handbook of cryptogamic botany. Cryptogams. FlG. I.—I., male catkin of Zamia (Cycadeae). II. III., antheriferous scale and pollen-sacs. FlG.^ 2.—Peltate scale of Eguisehtm^ with sporanges sg, (After Sachs.) sponding to the antherozoids, the pollen-grain itself becomes homologous with the microspore, the pollen-sac or anther-cell to the microsporange. Even in external appearance the pollen-sacs of Coniferse and Cycadeae bear a striking resemblance to the sporanges of some Vascular Crypto- gams. The modes of formation of the pollen-grains within the pollen- sac and of spores within the sporange, from an original archespore, are identical in their main features. Turning now to the female organs of reproduction, we must trace the homology of these back from the product of the union of the two elements, which in all the higher plants, whether flowering or flowerless, may be termed the oosperm, developing later into the embryo. In. 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 Bennett, Alfred W. (Alfred William), 1833-1902; Murray, George Robert Milne, 1858-. London, New York, Longmans, Green, and Co.
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