BEG 1 3 1929 
The influence of electrolytes on the tactical 
movements of Chlamydomonas 
Variabilis Dangeard 
by 
LIBRARY 
C. SPRUIT P.P.z00n. NEW YORK 
BOT ANICAL 
GARDEN 
PRÉFACE 
In my opinion, it is proved by the literature on the 
tactical movements of the unicellular organisms, how in 
physiology they have not been able to come into contact 
with chemistry and physics by a terminology of their 
own and a special method. 
This investigation should be looked upon as an attempt 
to change this. 
To begin with, it was necessary to find a sin table 
method. I think that the denoted way of working is a 
practical one. Moreover it can be proved by this investi- 
gation, that it is necessary to examine in detail the tactical 
phenomena. 
There must not be put too great value on the con- 
templations which arose from the comparison of the 
phenomena investigated by me with Chlamydomonas and 
those, which occur in colloïd-chemistry. 
To begin with the collected data are limited, though 
the number of experiments made amounts to two or 
three thousand. 
Recueil des trav. bot. néerl. Vol. XVII. 1920. 9 
