1915] 



MERRILL ELECTROLYTIC DETERMINATION OF EXOSMOSIS 



551 



solutions on the exosmosis from plant roots in order to obtain 

 a basis of comparison with the other agents used. 



In this connection it might be well to consider more in de- 

 tail the work of Lillie already referred to in the historical 



TABLE VIII 



CONDITION OF PLANTS EIGHT DAYS SUBSEQUENT TO TREATMENT WITH LOW 



CONCENTRATIONS OF ANESTHETICS FOR THE ENTIRE PERIOD 



Culture no 



28 

 29 



30 

 31 

 32-34 

 35 

 36 



Condition of tops 



Somewhat subnormal 

 Almost normal 



Dead 



Almost dead 



Practically dead . . 

 Practically normal 

 Practically normal 



Condition of roots 



Slightly flaccid 

 Considerably flaccid; tips 



less flaccid than in No. 



28 but upper part more 



so 



Considerably flaccid 



Very flaccid 

 Very flaccid 

 Practically normal 

 Somewhat flaccid 



review. His work on Arenicola and the eggs of Arbacia per- 

 tains largely to the exosmosis of the pigment and the man- 

 ner in which they were affected by isotonic salt solutions alone 

 and in the presence of various anesthetics. From the effect 

 observed, he concluded that the salts have a permeability-in- 

 creasing effect on the plasma membrane which is counteracted 

 by the anesthetics. But in dealing with the question of per- 

 meability it would seem that we must take into consideration 

 the effect on the exosmosis, not only of any contained pig- 

 ment, but of electrolytes as well. 



It would have been exceedingly interesting, and would have 

 furnished a means of strengthening or shattering his hypoth- 

 esis, as the case might be, had Lillie also measured the elec- 

 trical conductivity of the medium in which the Arenicola 

 larvae and the Arbacia eggs were placed and thus determined 

 whether the electrolytes contained in these organisms behaved 



as did the pigment 

 ('03), Peters ('04), 



It would seem that the work of Loeb 

 and others might be considered as sug- 

 gesting possibilities for electrolytic determinations along this 

 line with marine organisms. Without such facts at hand any 

 general conclusions in regard to permeability effects based on 

 the coloring matter only must be considered imperfect. What 



