20 
proteosomes in the contracted vacuole and explains this 
by assuming that on the death of the protoplasm the 
active protein is changed into passive and that then no 
more proteosomes can be formed, so that a vital reaction 
in given no longer. 
Without considering this explanation for the present, 
[ content myself with pointing out that, when the above 
experiments are repeated, careful observation already shows 
that so far as the localisation of the precipitate is concerned, 
Bokorny's view, accepted by Klemm, is incorrect. 
When first abnormal phasmolysis is produced with a 
10 ‘/, solution of potassium nitrate and this is followed by 
application of a 10!°/, solution of potassium nitrate which 
contains in addition 1 ‘/, antipyrine or 0.1 °/, caffeine or if 
a rod with ammonia is then held above the preparation, 
precipitation takes place exclusively in the contracted vacuole. 
If the reagents are allowed to act simultaneously or in 
reverse order, i.e. if the precipitation is first produced by 
the antipyrine or caffeine solution and followed by abnor- 
mal plasmolysis, then it is seen that the contraction of the 
vacuole is accompanied by continued expulsion of the pre- 
cipitate which is surrounded by cytoplasm. If the whole 
process is not followed under the microscope, but if the 
final result alone is observed, then it is easy to imagine 
that precipitation has also taken place in the cytoplasm 
and thus to draw an erroneous conclusion, as did Bokorny. 
As already mentioned, some investigators have obtained 
all possible protein reactions with the intravital precipitates, 
whilst others have only got negative results. Ï may remark 
that protein reactions at our disposal are in general not 
sensitive as microchemical reactions. When these reactions, 
namely, the test with sugar and sulphuric acid, the biuret 
test, Millon's test and the nitric acid test, are tried on 
minute pieces of coagulated egg-white, the various colora- 
tions can indeed be easily seen, but yet it is noticed that 
