. Plants; a text-book of botany. Botany. no PLANT RELATIONS. 72. Spore reproduction.—Besides vegetative multiplica- tion most plants develoj) special reproductive bodies, known as spores, and this kind of reproduction is knovi^n as spore reproduction. These sfiores are very simple bodies, but have the power of joroducing new individuals. There are two great groups of spores, differing from each other not at all in their powers, but in the method of their production by the parent plant. One kind of spore is produced by dividing certain organs of the parent; in the other case two special bodies
. Plants; a text-book of botany. Botany. no PLANT RELATIONS. 72. Spore reproduction.—Besides vegetative multiplica- tion most plants develoj) special reproductive bodies, known as spores, and this kind of reproduction is knovi^n as spore reproduction. These sfiores are very simple bodies, but have the power of joroducing new individuals. There are two great groups of spores, differing from each other not at all in their powers, but in the method of their production by the parent plant. One kind of spore is produced by dividing certain organs of the parent; in the other case two special bodies of the parent blend together to form the spore. Although they are lioth spores, for convenience we may call the first kind spores (see Figs. 106, 10'.)), and the second kind eggs (see Fig. 107).* The two special bodies which blend to- gether to form an egg are called gametes (see These terms are necessary to any J\Iost plants develop. Fig. 107. Fragments of a, common alga {Spi- rogyra). Portions of two threads are shown, which have been joined together by the grow- ing of connecting tubes. In the upper thread four cells are shown, three of which contain eggs (s), while the cell marked g, and its mate of the other thread each contain a gamete, the lower one of which will pass through the tube, blend with the upper one, and form another egg. Figs. 107, 108, 109). discussion of the external relations both spores and eggs, but they are not always equally con- spicuous. Among the algse, both spores and eggs are prom- inent ; among certain fungi the same is true, but many fungi are not known to jDroduce eggs ; among moss-plants the spores are prominent and abundant, but the egg is concealed and not generally noticed. What has been said " It is recognized that this spdre is really a fertilized egg, but in the absence of any accurate simple word, the term egg is used for con- venience,. Please note that these images are extracted from scanned page images that may have been digit
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