Organography of plants, especially of the archegoniatae and spermaphyta . ordiumis always visible between the sti-pules. A corresponding case is onlyknown to me in the inflorescence ofAmiciaZygomeris where the stipulesof the bract-leaves of the flowers aredeveloped as protective organs whilstthe lamina itself is arrested. C. Hypsophylls formedBY THE Leaf-base or mainlyso. Where this happens the seg-mentation of the leaf-primordiuminto leaf-base and upper leaf pro-ceeds gradually, and finally the leaf-primordium without reaching thestage of expansion as a leaf-laminabecomes sh^ath-like. This pr
Organography of plants, especially of the archegoniatae and spermaphyta . ordiumis always visible between the sti-pules. A corresponding case is onlyknown to me in the inflorescence ofAmiciaZygomeris where the stipulesof the bract-leaves of the flowers aredeveloped as protective organs whilstthe lamina itself is arrested. C. Hypsophylls formedBY THE Leaf-base or mainlyso. Where this happens the seg-mentation of the leaf-primordiuminto leaf-base and upper leaf pro-ceeds gradually, and finally the leaf-primordium without reaching thestage of expansion as a leaf-laminabecomes sh^ath-like. This processis found especially in plants withwell-developed leaf-base. In Rhi-nanthus we have, as has been aboveshown, an analogous example in thecase of leaves which are very slightlysegmented. A few examples fromplants with highly segmented leavesmust now be cited :—Mulgedium macrophyllum, Mulgedium macrophyllum, representedin Fig. 260, /, possesses at first a foliage-leaf whose lamina is plainly de-limited from the leaf-stalk, and the latter is winged in its upper Fig. 260. Mulgedium macrophyllum. Transition, inthe sequence / to IV^ from foliage-leaf to HYPSOPHYLLS 395 The leaf in Fig. 260, // is one from the lower region of the hypsophylls,and in it the leaf-stalk is scarcely indicated, but the leaf-base is enlargedevidently in correspondence with its function of protecting the inflorescence-bud which is thicker than an ordinary foliage-leaf-bud. The leaf in , /// has the limit between leaf-lamina and leaf-base still markedby a deep constriction. No leaf-stalk is present. Fig. 260, IV showsa leaf in which the limit between lamina and leaf-base is scarcely at allshown, and in leaves standing higher up the distinction disappears alto-gether. This transformation is easily understandable when the history ofthe development of the leaf is followed. All these leaf-forms resemble oneanother in their primordial stage, and the hypsophylls arise by the ar
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