INJUKY, EECOVERY, AND DEATH 



third, fourth and fifth days, the same experiment was 

 repeated four times. On the fifth day the tissue appeared 

 to be in as good condition as the control, and had a 

 resistance which was slightly higher. There was no 

 reason, therefore, to suspect that the changes in permea- 



DAY 





80 



\ \ /\ /\ 



HOUKS 



FIG. 35. Rise of net electrical resistance of Laminaria aoardhii in 1000 cc. eea water pluB 

 sufficient La(NOa)s to make the concentration 0.002 M (unbroken line) and subsequent fall 

 on replacing in sea water (broken line). Lower horizontal broken line represents the control 

 in sea water. The same lot of tissue was exposed four times daily on five successive days to 

 the action of La(NOs)a. All readings were made at 20 C. or corrected to this temperature. 



Each curve represents a single experiment. 



bility had been attended by any permanent injury. The 

 results are shown in detail in Fig. 35. 



Similar experiments were performed in which CaCl 2 

 was used in place of La (N0 3 ) 3 . In this case 3.3 gm. CaCl 2 

 were added to each 1000 cc. of sea water. Owing to the 

 fact that the rise in resistance took place more slowly 10 



10 



'If in place of solid CaCl 2 a strong solution is added, the rise is more 

 rapid and reaches a higher figure. 



