Organography of plants, especially of the archegoniatae and spermaphyta . shall have opportunity to return to thissubject again when dealing with striking similarity observable between thesterile shoot-axes of plants like Heleocharis^and Scirpus lacustris and the cylindric leaves ofa\on|°shootTnTLIverfeaion. ^of J uncus—these were formerly therefore desig-nated sterile culms—and the fact that all these plants live under essentiallythe same conditions have led to the supposition that the conformation of theassimilation-organs is utilitarian in both cases. The leaves of
Organography of plants, especially of the archegoniatae and spermaphyta . shall have opportunity to return to thissubject again when dealing with striking similarity observable between thesterile shoot-axes of plants like Heleocharis^and Scirpus lacustris and the cylindric leaves ofa\on|°shootTnTLIverfeaion. ^of J uncus—these were formerly therefore desig-nated sterile culms—and the fact that all these plants live under essentiallythe same conditions have led to the supposition that the conformation of theassimilation-organs is utilitarian in both cases. The leaves of the species ofScirpus were perhaps not in a condition to take on the cylindric form andexperienced, in consequence, a reduction in formation with a correspondingdiminution in function-. In many of these Monocotyledones it can be shownthat the leaf-formation may again set in under conditions which are unfavour-able to the formation of assimilating shoots, and we have here then essentiallya reversion to the juvenile stage^. Scirpus lacustris* for example forms long. ^ These consist of one long shoot-internode at the end of which a couple of scales is found if noflowers develop. On the rhizomes there are kataphylls only. In Cyperus alternifolius the elongatedshoot-axis bears foliage-leaves. Here also perhaps originally there were inflorescences which in thefirst developmental stages of the plant suppressed their flower-formation and appeared as strengtheningshoots. From the same standpoint we may regard the first still flowerless shoots that appear aboveground in Polygonatum, Paris, and like plants, and it seems to me this gives us a more comprehensiveview of the construction of these plants in which a process similar to that in the Cladonia amongstthe lichens (Part I, p. 72) may have taken place—first of all the fructification was raised upon a stalkand then vegetative activity set in within it. See what is said about the formation of phyllodes, p. 353. ^ .See Part I, p.
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Keywords: ., bookcentury1900, bookdecade1900, bookido, booksubjectplantanatomy
