igii] E. Newton Harvey 231 



Despite the fact that the group o£ streng alkalies encounter a 

 marked barrier at the surface of the cell and, in fact, fail to enter 

 before fundamentally modifying the nature of the surface, they 

 nevertheless produce changes in the normal functional activity of 

 the cell without entering. When Paramcecium is placed in any 

 alkali a certain series of changes ensues. Usually the avoiding 

 reaction is given, followed by a change in shape, swimming back- 

 ward, very slow swimming, the appearance of clear droplets at 

 the surface, the fusion of the droplets to a more or less clearly de- 

 fined membrane with cessation of movement and finally the burst- 

 ing of the motionless and much distorted organism. Only after all 

 motion has ceased and the Paramcecium is formless and dead, does 

 NaOH pass in and convert the red granules to yellow ones. The 

 decolorization, when once started at the surface, rapidly progresses 

 to the interior as the alkali enters. Other strong alkalies [K, 

 Ca, Ba, Sr and N(C2H5)40H] behave as does NaOH. NH^OH 

 and the amines, on the other band, begin to diffuse inward from the 

 moment the organisms are placed in the Solutions and the latter be- 

 come completely colorless before the clear droplets appear at the 

 surface. The difference in permeability cannot be explained by a 

 difference in combining power of NaOH and NH4OH but must 

 be referred to an influence of the NaOH on the surface of the cell 

 independently of any action on the cell interior. 



Protoplasmic rotation in the leaf cells of Elodea ceases long 

 before enough NaOH has entered to turn the neutral red yellow, and 

 irregulär fragmentation and division of echinoderm eggs may also 

 be induced without the entrance of NaOH.^ Such a surface change 

 may be in three conceivable directions: surface tension, electrical 

 polarization and permeability. The alteration in the latter property 

 is in the direction of an increase, since finally the inorganic alkali 



"Warburg {Zeit, für physiol. Chemie, 1910, Ixvi, p. 305) in a paper on oxlda- 

 tion, which I have but recently read, since its title gave no hint that the question 

 of permeability was discussed, showed that NaOH fails to enter sea urchin 

 eggs stained in neutral red whereas NH4OH does, and further that neutral red 

 is a more delicate test for the presence of OH ions than increased rate of oxida- 

 tion. In sea water plus NH4OH the red dye is affected, yet oxidations in the 

 eggs are hardly increased over the rate of oxidation of eggs in neutral van't 

 Hoff's Solution. In sea water plus NaOH the rate of oxidation is very mark- 

 edly increased. 



