Immunity of Loiuer Organisms to Ethyl Alcohol 575 



Richardson ^° in determining the death-point for a fresh-water 

 medusa found that from 3V per cent to tV per cent of alcohol 

 proved lethal to this form within a short period of time. 



Reid Hunt^^ in his fascinating Studies in Experimental Alcohol- 

 ism has obtained in higher animals the first positive evidence, so 

 far as I am aware, of direct injury due to minimal doses of alcohol. 

 These experiments upon white mice made it evident that amounts 

 of ethyl alcohol far too small to produce indications of intoxication 

 are capable of rendering the animal more susceptible to a definite 

 poison, — acetonitrile. 



In my experiments I have found protozoa comparatively resist- 

 ant to weak concentrations of alcohol. In solutions of i per cent 

 or lower, the organisms often lived in a prosperous condition for 

 weeks at a time. Solutions of alcohol as high as 4 per cent in 

 strength were in all cases early destructive of the protoplasm of 

 Stentor and percentages of 2 and 3 per cent produced death after 

 a period of six and two hours, respectively. 



B Reaction to Stronger Percentages 

 I Description 



In the following study two very different strains of Stentor — 

 which we may designate as E and F — ^were employed. These 

 showed marked differences in their reactions to ethyl alcohol. 



Type E, composed of cells of immense size, deeply pigmented, 

 and actively free-swimming, came from a black infusion of de- 

 cayed vegetable material. Type F on the other hand — composed 

 of cells of medium size, and usually attached, grew in a clear 

 medium of tap water and Chara. These latter cells maintained 

 a sturdy condition with slow rate of division for long periods of 

 time. 



The two types in a sublethal medium (e.g., i per cent alcohol) 

 showed the following characteristic differences in behavior. The 

 large cells E upon subjection to the alcohol were stimulated to 



»» Richardson, 1888 (July), Asclepiad. 



" Hunt, Reid, 1907, Bull. No. 33, Hyg. Lab. U. S. Pub. Health and Mar. Hosp. Serv., Washington, 

 D.C. 



