174 
When we ask for the cause of the different behaviour 
of the algae from different cultures, we can be sure, that 
the electrolyte concentration of the various cultures is not 
always the same. It is true the irregularities in this respect 
were diminished by preparing the cultures fluids with a 
special quantity of sterilized earth, white of egg and 
tapwater. The fact, however that the putrefaction of the 
eggwbhite did not always take place with the same quickness, 
must cause, that for example the quantity of ammonium- 
carbonate has not always been equally great in the different 
cultures. To this is added, that the whole treatment of 
the algae, before transporting them into the solution, 
whose influence was examined, aimed at taking away 
superficial defilement and to take care that the fluid, which 
had to be examined, would not be changed by a mixing 
up with small quantities of the culture-fluid. More effective 
changes were always avoided during preparation, so that 
we can accept, that the algae were used in the state, in 
which they were in the cultures. Important changes cropped 
up, when the stay in the distilled water lasted more than 
half an hour. 
The organisms then became much more susceptible to 
salts. Perhaps one is inclined to look upon this change 
by distilled water as an injurious action. It is not necessary 
for us to go against this opinion. However we can ob- 
serve, that the expression “injurious action” does not 
bring us much further. Î imagine the action of distilled 
water, to be totally different. AÏl we know as yet of the 
conduct of Chlamydomonas in regard to electrolytes 
points to the fact, that the influence of the dissolved sub- 
stances on the protoplasm is a colloïdchemical one. With 
acids and bases the plasmcolloïds form compounds which 
are chemical compounds probably. With neutral salts are 
probably formed absorption compounds Starting from these 
suggestions, we think that the changes by a long washing 
