W. J. V. OSTERHOUT 



153 



tissue is allowed to remain in the solution for a short time and is then 

 replaced in sea water the resistance falls rapidly, as shown in Fig. 2. 

 This fall of resistance may be regarded as analogous to the rise of 

 resistance which occurs in the experiments with NaCl and the term 

 recovery may be used in both cases. It is evident from the figure 

 that, as the exposure to the solution of CaCl2 lengthens, the level 



eOOmin. 



Fig. 2. Curves showing the rise and fall of electrical resistance in Laminar ia 

 agardhii in 0.278 M CaCl2 (single curve which rises and falls) and recovery in sea 

 water (descending curves). The figure attached to each recovery curve denotes 

 the time of exposure (in minutes) to the solution of CaCl2. 



In the recovery curves the experimental results are shown by the dotted lines, 

 the calculated results by the unbroken lines. 



The observed points represent the average of eight or more experiments. 

 Probable error of the mean less than 10 per cent of the mean. 



