May. 1919.] 7. NAOAI.- GEMMJE OF MA RCHANTIA. 1 07 



be pulled out the vicious protoplasmic colloid complex, and the move- 

 ment due to Brownian movement of molecules. A careful examination 

 was made with the cells of prothallia of Aspknium Nidus, the gemma; of 

 Marchantia polymorpha and the epidermis of the leaf of Tradescantia 

 sp. Most of the points described by the previous investigators were 

 confirmed except those which were only visible under dark-ground 

 illumination that was employed by some of the authors. 



It may incidentally be mentioned here that the fibriles in the cell of 

 Aspknium and Tradescantia showed a rapid change in structure. They 

 appeai-ed more or less homogeneous at first, even they often carried 

 granules. In rapid wavy motion, the\' became granular and finally 

 showed as if the stretched beads of spherules. These spherules increased 

 in size gradually. Sometimes larger ones were formed on the surface 

 of the contracted protoplasmic mass in the cell of Tradescantia. They 

 seemed to be the vacuolated protoplasmic colloid probably formed by 

 the change in the surface tension of stretched liquid film. 



The protoplasmic net-work on the wall of cell which was described 

 by Hecht was considered by Price as "little jDatches or disc of proto- 

 plasm composed of very fine particles" and "at the end of the fibriles 

 which are in some instance pulled out with a little V-shaped piece." 

 Despite of minor disagreements, all seemed to agree with the formation 

 of gel membrane on the surface of plasmolyzed protoplasmic colloid 

 which was in a state of sol. Even after plasmolysis is recovered, the 

 protoplasm is covered with the gel membrane and with such proto- 

 plasmic discs and fibriles already described. The colloidal state of the 

 surface of protoplasm altered by j^lasmolysis may ensue a reversible 

 change and it must surely do so where the fusible protoplasmic pieces 

 are formed (Kuster : 1910), but the fibriles and discs may possibly 

 remain as they are, at least for some time. The change in the surface 

 phenomena after plasmolysis may be the chief factor in induction of 

 adventitious growth. It is of interest to recall the view of Noll (1903) 

 that the peripheral layer of protoplasm is the seat of "Gcstaltungs- 

 dominanten." 



Dorsiventrality of the gemmae of Marcliantia is rigorously main- 

 tained. VoCHTiNG was led to suppose that ,,das lebendige Geriist der 

 Brutknospe aus Molekelketten bestcht, die symmetrisch zu den drei 

 Durchschnittsebenen angeordnet, und deren einzelne Glieder parallel zur 

 grossen Axe des Korpers polarisiert sind," and ,,dass die Ketten nur an 

 einem, dem der neutralen Ebene abgewandten End freie Aflfinitaten 

 bcsitzen." By means of plasmolysis the inner co-ordination is in some 



