AN ARTIFICIAL OSMOTIC CELL 



43 



the prepared solution are placed upon it. After the desired 

 amount of growth has taken place, the slide is lowered into the 

 vessel, moved briskly, to wash off the solution, and allowed to 

 remain in the water until all the KMn04 is washed out of the 

 osmotic sacs. The preparation may then be mounted in glyceri- 

 nated gelatine. A series of such preparations, with different 



Fig. 1, A. Diagrammatic representation of various stages in the formation of 

 osmotic sac and tube. B. Representing the manner of growth at the tip of the 

 tube. Inside are shown small separate bodies, which became joined to form the 

 inner layer. The middle layer is shown in black, and the outer by shading. 

 C. General appearance of growth at surface of solution (floroid). D. Micro- 

 scopic appearance of the central part of the floroid, showing the closely crowded 

 open canals. Magnification 33 diameters. E. Bending of tubes toward wall 

 of vessel and beginning of annular formation. 



amounts of growth, constitutes a consecutive record of the 

 changes occurring in the process. 



As long as the stem is immersed in the solution and there is 

 a supply of KMn04 within, its upward growth continues. Ar- 

 rived at the surface of the solution — not too near the wall of 

 the vessel — a number of branches are formed, which grow hori- 



