536 



EDMUND NEWTON HARVEY 



outward while the NaOH cannot pass in to 7naintain the dye in the 

 yellow condition. Eventually of course the leaf in 5^ KOH be- 

 comes yellow just as does the control. 



The amines show a behavior similar to NH4OH but, with the 

 exception of trimethyl amine, are considerably more toxic and 

 produce after effects which lead to the death of the cell. The 

 entrance of just enough to affect the neutral red is typically fatal 

 (table 5). 



TABLE 5 



Effect of NH4OH and amines on red Elodea leaves. Concentration, ^j^ in glass distilled water. The 

 red color disappears (decolorized) in less than 2 minutes in all solutions. The leaves are then trans- 

 ferred to (A) tap water; (,B) y?^ NaOH. Columns A and B give the results, respectively. 



Leaves treated with CHCI3, after decolorization in any of the above solutions, and placed in jq NaOH 

 never become red again; if placed in tap water all tend to become red but the red dye eventually dif- 

 fuses out of the cells because the cell surface has been affected by the chloroform. 



c. Permeability of cells exhibiting protoplasmic rotation. There 

 appears to be no marked difference in the resistance of 'rotating' 

 and quiescent cells to the penetration of NaOH or KOH. In a 

 number of experiments in which individual cells were watched 

 rotating cells became yellow before non-rotating or vice versa. 

 Comparisons of whole leaves are not of much value because of their 

 great variability in resistance to NaOH. 



