PROTOPLASM OF PROTOZOA ^9 



found lived in ranges from pH 2.3 to pH 11. Studies on the effects of 

 hydrogen-ion concentration on protoplasmic viscosity are complicated by 

 the rate of entrance of the ions and by the fact that they may be neutral- 

 ized by the buffers of the protoplasm (Pollack, 1928a) . 



Pantin (1926a) has found that the movement of certain marine 

 amoebae takes place between /;H 6 and 10. It is reversibly inhibited at 

 the acid limit, but alkaline inhibition is reversible only after a brief Im- 

 mersion. The rate of movement he holds to depend upon the rate of 

 change in s6l:;:±gel transformation. In addition, the water content of 

 A. p rote us has been shown to vary with the hydrogen-ion concentration 

 of the medium (Chalkley, 1929). The effect of changes in hydrogen-ion 

 concentration upon the action of cilia has been studied by Chase and 

 Glaser (1930). 



THE EFFECTS OF NARCOTICS 



For a summary of the literature on the effects of narcotics in cells gen- 

 erally, the reader is referred to the work of Winterstein (1926) and of 

 Henderson (1930). In general it may be stated that the action of nar- 

 cotics upon cells is to change their permeability and viscosity, to inhibit 

 enzyme action, and to affect the electric potential. 



Alcohol has been reported to produce a lowering of the viscosity of 

 the protoplasm of A. proteus (Edwards, 1923; Brinley, 1928). Ether 

 and chloroform likewise have similar effects (Brinley, 1928). Certain 

 paraffin oils have also been reported to have a narcotic effect on A. dubia 

 (Marsland, 1933). More recently Daugherty (1937) found that the 

 higher alcohols and ether in concentrations just below lethal cause lique- 

 faction of the plasmagel of Amoeba; the same concentrations of the 

 lower alcohols produce gelatin of the plasmasol; the higher alcohols and 

 ether, liquefaction of the plasmasol. More dilute solutions of the higher 

 alcohols and ether produce first liquefaction and then gelatin of the 

 plasmasol (see also Frederikse, 1933a). Potassium salts and fat solvents 

 liquefy the plasmagel in A. proteus (Heilbrunn, 1931). 



Makarov (1935) has studied the effects of narcotics on various Infu- 

 soria, using vital stains in conjunction with the ultramicroscope. Narcotics 

 cause a change in the dispersion of the colloids, which is reversible. 

 Strong concentrations cause an irreversible coagulation. 



