PROTOPLASM .5 



STRUCTURE OF PROTOPLASM 



There is one fact about which there can be no doubt, that is, that protoplasm 

 behaves as a liquid. This is shown by the spherical form taken by drops of 





/-. 





.'I 



'Let 



FIG. 5. CELLS OF STAMINAL HAIKS OF TRADESCANTIA VIRGINICA. 



1. Normal cell a, cell wall; b, nucleus; c, protoplasm; rf, wave of contraction in 



protoplasm ; e, web-like plate arising from the fusion of two fine threads ; /, 

 moving bridge between two stronger protoplasmic currents. Length of cell, 

 0'3 mm. 



2. Somewhat younger cells excited by induction shocks parallel to long axis. 



A, shocks of moderate strength ; 6, stronger shocks. In C the protoplasm is 

 coagulated by rupture of cell and entrance of water. Length of cell A, 

 0'145 mm. 



(Kiihne, 1864, PI. i. figs. 1 and 4.) 



watery fluid when they are enclosed in it (Figs. 1 and 3). These drops must 

 therefore be free to take the form conditioned by surface tension, and hence no 

 fixed or solid structures can be present to deform them, unless these structures are 

 themselves freely movable. Further, when the fine particles, present in certain 



