Immunity of Lower Organisms to Ethyl Alcohol 591 



Type F illustrates this in a clear way. Animals of the same 

 strain kept under similar external conditions and for a like period 

 of time, varied at different times in their reactions to the same 

 concentration. Thus type F, kept in a I per cent medium for 

 four days, gave at different times average resistance periods to 6 

 per cent alcohol of 229.5, 301, 299.5 ^"^ 334 seconds — a differ- 

 ence of more than 100 seconds between the two extremes, though 

 their controls, 153.5 and 160, were practically equal at the dif- 

 ferent times. 



But not alone did type F show varying degrees of resistance at 

 different times when tested to the 6 per cent alcohol, but it mani- 

 fested to a more remarkable degree the same variability when 

 tested to a stronger concentration. Type E as we may recall, 

 while it showed unusually high resistance to a 6 per cent killing 

 fluid, showed low resistance when tested to 8 per cent. Type 

 F, on the contrary, though low to 6 per cent alcohol, sometimes 

 gave a resistance to 8 per cent which was but little short of that 

 given to a 6 per cent solution. 



This may be shown in the following experiment: 



Experiment XI a 



RESISTANCE OF STE.VTORS OF TYPE F TO 8 PER CENT ALCOHOL, AFTER LIVING 4 DAYS IN I PER CENT 



ALCOHOL 



A Four Days in I Per Cent 



Seconds 



Lxp. I cilia stop 315 



i cilia stop. 190 



3 cilia stop 380 



4 cilia stop 215 



5 cilia stop 1 60 



6 cilia stop 155 



7 cilia stop 120 



8 cilia stop 210 



9 cilia stop 210 



10 cilia stop 140 



Exp. 



1 c 



2 c 

 3 



5 a 

 6 



7 ci 



8 c: 



9 c 

 10 c 



C Control 



Seconds 



lia stop 135 



lia stop 150 



lia stop 85 



lia stop 160 



lia stop 100 



lia stop 135 



lia stop 30 



lia stop 135 



lia stop 95 



lia stop 90 



209.5 



III. 5 



Finding the normal resistance so high, I was interested to see 

 whether acclimatization to a 0.5 per cent solution would show, 



