160 Autonomy of Cell-Organs 



ledges, jutting into the interior, are in the process of for- 

 mation there generally run strong currents which evi- 

 dently bring and distribute the requisite food. But this 

 differentiation in the granular plasm is, to all appearances, 

 controlled by a corresponding differentiation in the plas- 

 matic membrane. For, according to Dippel, the bands 

 which form the layers of cellulose, consist of an outer 

 hyaline band, which is thicker than the rest of the plas- 

 matic membrane, and, like the latter, cannot be stained 

 with iodine, together with an inner, moving layer of the 

 granule-bearing plasm, which takes a deep yellow tint 

 when treated with iodine.^^ The hyaline band is evi- 

 dently a differentiated part of the plasmatic membrane 

 which, on its inside is covered and nourished by the cur- 

 rent, and on its outside forms the ledges of the cell- 

 membrane.^^ 



In naked protoplasts the cilia also bespeak an inner 

 organization of the plasmatic membrane. These are de- 

 scribed by Strasburger^^ for the swarm-spores of Vmt- 

 cheria. Here all the cilia adhere to a denser part of this 

 layer; they appear to be embedded in it by a thick root. 



8. The Question of the Autonomy of the Limiting 



Membrane 



While in cell-division, according to the type described 

 by Mohl, the multiplication of the limiting membrane by 



65Loc. cif. pp. 57, 58. 



^^Strasburger's hypothesis that the growth of the cell-wall is 

 accompanied by a transformation layer by layer of the outermost 

 strata of the limiting membrane into cell-wall can, without difficulty 

 be combined with the assumption of the autonomy of this organ with 

 reference to the granular plasm, and therefore need not be discussed 

 in detail here. 



^''Strasburger, Studien iiber das protoplasma, p. 400. 1876. 



