. Plant studies; an elementary botany. Botany. 11(1 PLANT STUDIKS. 72. Spore reproduction.—Besides vegetative multiplica- tion most plants develop special reproductive bodies, known as spores, and this kind of reproduction is known as spore reproduclion. These spores are very simple bodies, but have the jiower of producing new individuals. There are two great groui^s of spores, diilering 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 jiarent ; in the other case two special bo
. Plant studies; an elementary botany. Botany. 11(1 PLANT STUDIKS. 72. Spore reproduction.—Besides vegetative multiplica- tion most plants develop special reproductive bodies, known as spores, and this kind of reproduction is known as spore reproduclion. These spores are very simple bodies, but have the jiower of producing new individuals. There are two great groui^s of spores, diilering 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 jiarent ; in the other case two special bodies of tlie parent l)lend together to form the spore. Although the}' are both spores, for convenience we may call the first kind spores (see Figs. lOG, 100), and the second kind cfjgs (see Fig. 107).* The two sjiecial liodies which lileud to- tjether to form effg are called gameten (see Figs. 107, lo,s, lOD). Tliese terms are necessary to any discussion of the external relations. Most plants develop both spores and eggs, but they are not always equally con- s])icuous. Among the alga^ both spores and eggs are i)rom- iuent ; among certain fungi the same is true, liut many fungi ai'o not known to produce eggs ; among moss-phmts the si)ores prominent and abundant, but the egg is conceale(l not generally noticed. AVliat lias l)eeu said •'" II is rccoij'iuzed that this spore is i-cally a. fertilized egg, but in tlic abseiici' of any accurate simple word, the term egg is used for con- venience. Fli;. 107. of a common alga {Sin- rogyrii). Portions of two threads are shown, wliicli have been joined together l)y the grow- ing of connecting tubes. In tile upper thread four cells are shown, three of which contain eggs (,:), while I ho cell marked g, and its mate of the other Ihroad each contain a gamete, the niii' of whii'h will pass through the tiilie, hli-iid with the upper one, and form another Please note that these images are extracted
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