141 
on the effect of CaCl,; on the other hand CaCL has an 
enormous influence on KCC. CaCL, has no influence on 
K,SO,. It is clear that the valence and the sign of the 
ions defines their mutual influence. In calloïd chemistry we 
can find back a similar state of things. If we do not see 
any connection between the colloïdchemical phenomena 
and the chemotaxis we cannot but side with Kniep in 
his opinion, that the organism for different chemotactica 
holds different sensibilities unless one accepts that different 
chemotactica need a different reaction-time. 
I believe that by this is sufficiently proved the right 
claim of a colloïd chemical treatment of the chemotactical 
phenomena. 
If indeed colloïd chemical processes act such a great 
part with the chemotaxis, it is a matter of course to 
suggest, that there are no specific chemotactica. It is 
problable that all electrolytes exercise their influence, 
though those, called chemitactica, shall have a very great 
effect. Kniep's data agree with this opinion. So do his 
discoveries with spirillum rubrum. Spirillum rubrum did 
not react to nitrates. Meanwbhile nitrates were able to 
diminish the effect of chlorides. 
Starting from the opinion that there are no specific 
chemotactica, we begin with controlling the conduct of 
experiment-organisms towards solutions of electrolytes, 
which act on all sides. If we know all about this, we 
must try to make out, whether the conduct shows pecu- 
liarities towards the electrolytes, defined as chemotactica. 
