ASYMMETRIC ANALYSIS 



107 



Further, in experiments on the toxic action of opti- 

 cally isomeric einchonines upon paramecia, it was found 

 that the laevorotatory isomer inhibits the mechanism of 

 ciliary movement more rapidly than does the dextro form 

 (Gause, Smaragxlova and Alpatov, 1938). The dynamics 

 of toxic action in dextro and laevo einchonines were found 

 to be identical (cf. Fig. 15). A study of the temperature 

 characteristics of toxicity has also shown that these are 

 practically identical, 14,200 in the laevorotatory and 

 14,000 in the dextrorotatory isomer (cf. Fig. 16). 



14 16 I 8 2 2 2 



Log. of effective concentration {.v-)i) 



Pig. 15. Killing action of the optical isomers of cinchonine on 

 Paramecium caiulatum. The lower graph represents the toxicity curves 

 in logarithmic coordinates. (From Gause, Smaragdova and Alpatov, 

 1938). 



