HEAT RESISTANCE OF PARAMECIUM 



215 



combination of NaCl and CaClo. When the Paramecia were 

 transferred to a medium consisting of 10 cc. of M/lOO NaCl 

 plus one drop of M/lOO CaCl2 the results shown in table 4 were 

 obtained. 



TABLE 3 



The effect of M/3000 CaCh on the heat resistance of P. caudatum from an alkaline 



medium 



IN M/3000 cacl2; sum of four 



EXPERIMENTS 



Totals subjected to each temperature. . 



Number of deaths 



Percentage dead at given temperature. . 



controls: unchanged medium, four 

 experiments 



Totals subjected to each temperature. . 



Number of deaths 



Percentage dead at given temperature. . 



TEMPEH.^TURES 



39° 



286 

 







444 

 

 



40° 



340 

 

 



409 

 58 

 11.7 



41° 



276 

 

 



316 

 314 

 99.3 



42° 



357 

 194 

 54.2 



554 

 554 

 100 



43° 



319 

 310 

 97.1 



44° 



320 

 320 

 100 



MEANS OF THE ABOVE FATAL 

 TEMPERATURE ZONES 



/ in M/3000 CaCL 41.98' 



1 in controls 40.3° 



TABLE 4 



The effect of NaCl plus CaCU on the heat resistance of P. caudatum from an alkaline 



medium 



ME.\NS OF THE ABOVE FATAL 

 TEMPERATURE ZONES 



/ in NaCl + CaCl. 42.56° 



\ in controls 40.3° 



