1918] 
BONNS—ETHERIZATION AND ENZYME ACTIVITY 241 
the cell membranes to the respective substances. Chiari 
(709) reported that ether, chloroform, and other narcotics in- 
creased autolysis of canary’s liver, and he ascribed this ef- 
fect to the solvent action of such substances upon the lipoid 
constituents of the cell membrane; by such action, he believed, 
enzymes acting upon cell contents penetrated the membrane 
more easily. Czapek ('10), in his studies on exosmosis with 
reference to permeability and surface tension, found that ex- 
posure of Echeveria cells to chloroform for twenty-four 
hours produced an alteration in the permeability of the 
plasma membrane, resulting in the absence of certain pre- 
cipitation phenomena when treated with caffein. Ether had a 
similar effect; short periods of narcotization up to one hour 
had no such action. 
Lepeschkin (711), in a study of the chemical composition of 
the plasma membrane, showed that substances readily soluble 
in oil and poorly soluble in water, of the class designated as 
narcotics by Overton, were held in the dispersion phase of 
the plasma membrane, and that a proper concentration of 
such eompounds in the aqueous solution bounding the cells 
may reach a point where resulting electric changes produce 
a protein coagulation. This in turn affects the selective per- 
meability of the plasma membrane. With smaller concentra- 
tions of narcotics in the external medium the chemical com- 
position of the dispersion phase of the membrane would also 
be changed, so that a certain amount of narcotic would be 
taken up. Believing that the osmotie properties of mem- 
branes must be altered by such action, Lepeschkin (’11*) 
made experiments to determine this point. Aniline dyes, with 
varying solubility properties in water, chloroform, and ether, 
were used, and Spirogyra cells served as indices of perme- 
ability. Etherized algae took up the methyl dyes from 
aqueous solutions to a lesser degree than the controls. That 
this action indicated an alteration in membrane permeability 
was shown by an equal staining of etherized and control fila- 
ments previously killed. 
Another experiment showed permeability alteration in rela- 
tion to salts by the isotonie coefficient method, the plasmo- 
