Note 55 — THE INDIVIDUAL ORGANISM WITH REGARD TO FORM AND METABOLISM (continued 2)

For a good discussion of “super-regeneration” in the roots of plants see Němec, Studien über die Regeneration, Berlin, 1905. Goebel and Winkler have succeeded in provoking the “restitution” of parts which were not removed at all by simply stopping their functions (leaves of certain plants were covered with plaster, etc.). (Biol. Centralbl. 22, 1902, p. 385; Ber. Bot. Ges. 20, 1902, p. 81.) A fine experiment is due to Miehe. The alga Cladophora was subjected to “plasmolysis,” each cell then formed a new membrane of its own around the smaller volume of its protoplasm; after that the plants were brought back to a medium of normal osmotic pressure, and then each single cell grew up into a little plant (all of them being of the same polarity!). Two questions seem to be answered by this fact: loss of communication is of fundamental importance to restitution, and the removal of mechanical obstacles plays no part in it, for the mechanical resistances were the same at the end of the experiment as they had been at the beginning. (Ber. Bot. Ges. 23, 1905, p. 257.) For fuller analysis of all the problems of this chapter see my Organische Regulationen, my reviews in the Ergebnisse der Anatomie und Entwickelungsgeschichte, vols. viii. xi. xiv., and my Boston address mentioned above. Compare also Fitting, Ergebn. d. Physiol. vols. iv. and v.