ON PROTRUSION OF PROTOPLASMIC FILAMENTS. 



257 



currents in the water in which they are mounted, observation 

 would be difficult, at least, with Velten's apparatus; but this is not 

 the case, for I have often seen the filaments violently shaken by 

 the current without contracting. In the following experiments I 

 thought it necessary to give the time at which the various tem- 

 peratures were attained, because Kiihnei has shown that time is 

 an important element in heat experiments on protoplasm. 



Experiments with Velten's apparatus. 

 In both I and 2 the record of experiment begins when the 

 vessel had been filled with warm water. 



Experiment 1. — Aug. 19th. 



'Das Protoplasma,' 1864, p. 103. 



