6o2 J. Frank Daniel 



nounced contortions of the protoplasm were the forerunners of a 

 wave-like action which passed posteriorly, splitting away the endo- 

 plasm from the pellicula and forming of the endoplasm a typical 

 coagulum. As a result of this action, all ciliary movement ceases, 

 excepting that of the buccal pouch. (At this location, pellicula 

 and endoplasm were not early separated.) 



Destruction came about more rapidly in the case of acclimatized 

 animals than of the controls; this may be seen from the following 

 experiment upon resistance (Stentor). But the reason for a much 

 earlier splitting and coagulum formation in the one case than in the 

 other is by no means clear. 



2 Effects Upon Resistance 



In the following experiments upon both Stentor (type F) and 

 Spirostomum, a notable difference was seen between normal and 

 acclimatized animals when tested as to their endurance in a lethal 

 dose of hydrochloric acid. 



In both cases the acclimatized animals were reared in a I per 

 cent medium of alcohol. These at the end of four days showed 

 an increased resistance to 6 per cent alcohol. They were then 

 tested to -g~^ and yf ^ concentrations of HCl, respectively. 



Experiment XVI 



RESISTANCE OF STENTOR AND SPIROSTOMUM TO Hcl AFTER ACCLIMATIZATION IN A I PER CENT SOLUTION 



OF ALCOHOL 



a Stentor h Spirostomum 



Tested in ^m^- Sol. HCl Tested in ^m_ Sol. HCl 



AC AC 



Acclimatized Control Acclimatized Control 

 to Alcohol to Alcohol 



Seconds Seconds Seconds Seconds 



Exp. I cilia stop 60 170 Exp. i cilia stop 150 150 



2 cilia stop 2X0 210 2 cilia stop 160 160 



3 cilia stop 180 230 3 cilia stop 140 140 



4 cilia stop 50 180 4 cilia stop 180 180 



5 cilia stop 40 140 5 cilia stop 160 235 



6 cilia stop 40 285 6 cilia stop 155 150 



7 cilia stop 40 270 7 cilia stop 140 160 



8 cilia stop 50 195 8 cilia stop 200 180 



9 cilia stop 70 390 9 cilia stop 145 260 



10 cilia stop 45 420 10 cilia stop 160 170 



Average resistance. ...= 78.5 249 Average resistance. ... = 159 178.5 



