AUTHOR S ABSTRACT OF THIS PAPER ISSUED 

 BY THE BIBLIOGRAPHIC SERVICE, JDLT 11 



THE TOXICITY OF ACIDS TO INFUSORIA 



III. ANTAGONISM OF THE TOXIC ACTION OF ACIDS BY INORGANIC 



CHLORIDES 



M. E. COLLETT 



Clark University and University of Buffalo Medical Department 



TWO FIGURES 



As a means of determining the way in which acids act in 

 attacking the Hving cell, the following experiments have been 

 made in which the acids are combined with varying amounts of 

 certain inorganic chlorides. The experiments were performed at 

 Clark University and were undertaken at the suggestion of Dr. 

 R. S. Lillie, for whose help and interest I am exceedingly grateful. 

 The acids studied are as follows : 



Inorganic: HCl. 



Monobasic fatty: formic, acetic, butyric, caproic. 



Cyclic: benzoic, salicyhc, phenylacetic, succinic. 



Hydroxy: lactic, tartaric, citric. 



The concentrations chosen vary from acid to acid, but in every 

 case are such as will kill Paramecium in about two minutes and 

 Euplotes in less than twenty. The acids were tried alone and in 

 combination with the following chlorides : 



Alkali: NH4CI, NaCl, KCl. 0.01 -0.1 M 



Alkaline-earth: BaCla, CaClo, MgCls, SrCla. 0.001 -0.01 M 



Heavy metal: CdCl?, C0CI2, MnCla. 0.001 -0.01 M 



NiCla, ZnCla. . 0001-0 . OOIM 



The range of salt concentrations was selected to include not only 

 the optimal concentration, but also higher and lower concentra- 

 tions which are less efficient. The results are not the same with 

 all the acids, but in a general way two main groups are defined of 

 which acetic and caproic are types. 



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