yi^'vi/i//;77.'/r .i,v.i/.r.s7.s' 125 



TABLE 21 



Stereo-Coefficients of Action of the Optical Tso.mkus of Cinchoxine 



ox Vauioi's Functions in Paramecium caudatum. 



(Froji Gaise, Smaragdova and Alpatov, 1938.) 



Function Stereo-coefficient 



Inhibition of f 1. Formation of gastric vacuoles j ^ =: 1.36 



endoplasm ■{ 2. Release of gastric vacuoles 

 [ 3. Division rate 



ot = 1.36 

 a = 1.24 



Inhibition of \ 



ectoplasm ( 1. Mechanism of ciliary motion fi = ^-^^ 



The differences ol)served in the vakie of the stereo- 

 coefficient suggest that, in the ectophism, cinchonine in- 

 hibits a receptive substance diiferent from that of the 

 endophism. A physiological differentiation of the cells 

 into ectoplasm and endoplasm would then be brought into 

 evidence in Paramecium caudatum by our method of 

 ''asymmetric analysis". 



However, in another species of paramecia {Para- 

 mecium hursaria), the stereo-coefficients of the action of 

 optically isomeric cinchonines on various functions did 

 not disclose such a dilfereuce; the same stereo-coeffi- 

 cient of inhibition was observed for the endoplasmic and 

 ectopia smic function. 



For the study of the effects of the optical isomers of 

 cinchonine on the rate of movement of paramecia the 

 procedure Avas, in general, as follows. To 2 cc. of cin- 

 chonine solution of a given concentration 5 drops of a 

 culture of Paramecium caudatum were added. A little 

 quantity of the cinchonine solution with infusoria was 

 then transferred with a pipette into a thin glass tube 

 and the latter was placed on a graduated glass plate on 

 which the velocity of motion was measured with the aid 

 of a stop-watch. The determinations were made every 

 ten minutes for eighty minutes. 



While, for a time, no significant ditference in velocity 

 could be observed in the control and in the right isomer 

 solution, the paramecia in the left isomer of the same 



