Immunity of Lower Organisms to Ethyl Alcohol 6oi 



bulging and extrusion of the protoplasm, followed by a rapid loss 

 of color. The body cilia ceased moving early, but the membranellae 

 continued with strong stroke until nearly the time of death. 



Acclimatized Stentors, on the other hand, upon subjection to the 

 6 per cent alcohol usually remained motionless. Early distor- 

 tion, then uncertain beat of cilia up to 45 seconds, was followed 

 by an increase in ciliary activity. This finally became so vigorous 

 as to shake the whole body mass of protoplasm. In this, as in our 

 previous study, an extreme tenacity of life was manifest. 



Thus both in behavior and in chemical action differences were 

 produced. The relation the one bears to the other, however, is 

 difficult to see. 



Notwithstanding the fact that a stronger external effect was 

 produced upon the acclimatized animals than upon the controls, 

 the former survived a greater period of time in a lethal percentage 

 of alcohol than did those of the control animals. 



We may now examine the phenomena in acclimatized and con- 

 trol animals when hydrochloric acid is used as the killing fluid. 



B The Action of Hydrochloric Acid (HCl) 



I General Effects 



Unacclimatized Stentors tested to an ^^^ solution. In a concen- 

 tration of this strength an early rotation was noted which ceased 

 soon after injury began (15 to 30 seconds); the membranellae 

 stopped early. The body upon losing its color became brown. 

 A little later contortions of the protoplasm were followed by a 

 splitting away of the body mass from the cell wall and a forming 

 of this mass into a coagulum. 



After this action no ciliary motion was seen excepting in the 

 buccal cavity. 



Acclimatized Stentors. With the exception that a slightly greater 

 activity was shown in these than in normal Stentors no difference 

 either physiological or chemical could be detected. 



The most striking phenomenon of the above study, observed 

 both in normal and acclimatized animals, was the peculiar way 

 in which ciliary activity was stopped. Just before death, pro- 



