The dynamics of living matter . dynamicsofliving1906loeb Year: 1906 DYNAMICS OF REGENERATIVE PROCESSES 219 case of a piece from the body wall of an Actinian which has no digestive organs, the material of the new tentacle can come only from one of two sources, viz. from the chlorophyll (or parasitic algae?) which are con- tained in the ectoderm, or through a hydrolysis of material contained in the cells of the Actinian itself; this latter case would be comparable to Miescher's observation of the growth of the sexual glands at the expense of muscular tissue. In the case of the polyp formation i
The dynamics of living matter . dynamicsofliving1906loeb Year: 1906 DYNAMICS OF REGENERATIVE PROCESSES 219 case of a piece from the body wall of an Actinian which has no digestive organs, the material of the new tentacle can come only from one of two sources, viz. from the chlorophyll (or parasitic algae?) which are con- tained in the ectoderm, or through a hydrolysis of material contained in the cells of the Actinian itself; this latter case would be comparable to Miescher's observation of the growth of the sexual glands at the expense of muscular tissue. In the case of the polyp formation in Tuhularia, the transformation of the material of the stem into the polyp can be directly observed (Bickford, Driesch, and others). It is even doubtful in these cases whether a hydrolysis is necessary in any considerable amount, and it looks as if the tissues could be utilized directly for the formation of the polyp; some hydrolysis may however occur. In the above-men- tioned case of the transformation of a branch of Antennularia into a root, the polyps that were on that branch first disappear. I cannot make any definite statement as regards their fate, but it is not impossible that the material of the polyps is used for the formation of the new roots. I have observed more closely the transformation of an organ into more undifferentiated material in Campanularia, Fig. 62, a hydroid.* This organism shows a remarkable stereo- tropism. Its stolons attach themselves to solid bodies, and the stems appear on the side of the stolon exactly opposite the point or area of con- tact with the solid body. The stems grow, moreover, ex- actly at right angles to the solid surface element to which the stolon is attached. If such a stem be cut and put into a watch glass with sea water, it can be observed that those polyps which do not fall off go through a series of changes which make it appear as if the differ- entiated material of the polyp were transformed into undifferentiated material. The
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