Adventitious buds are also common on leaves (e.g. Bryophyllum, Ferns, etc.), and are frequently induced on them by wounds—e.g. Gesneria, Gloxinia, etc. Even cut cotyledons may develop them, and pieces of leafless inflorescence (Hyacinth), hypocotyl (Anagallis), and in fact practically any wounded tissue with a store of reserve materials may be made to develop them: thus they have been found arising from the pith of Sea-kale, and are commonly developed from the cut bulb scales of Hyacinths.
Apospory and Apogamy are particular cases of the production of vegetative buds on the leaves in place of sporangia in Ferns (Apospory), and on prothallia in place of Archegonia (Apogamy), in the latter case induced by dry conditions and strong illumination.
Notes to Chapter XXVIII.
In addition to the literature quoted in the [notes to Chapter XXVII.], the student should consult the works on Forest Botany for the scattered information regarding adventitious buds. A good account may be found in Büsgen, Bau und Leben unserer Waldbäume, Jena, 1897.
For Apospory and Apogamy, see Lang "On Apogamy and the Development of Sporangia upon Fern Prothalli," Phil. Trans., vol. 190, 1898, p. 187, where the literature is collected.
CHAPTER XXIX.
GRAFTS.
Grafting—Comparison with cuttings—Effects of environment—Relations between scion and stock—Variation in grafts—Grafting and parasitism—Infection—Pollination—Grafts-hybrids—Predisposition of Natural grafts—Root-fusions.