(739 ) 
power ought to rise, when larger quantities of pancreatic juice are 
used. For, it is well known that a characteristic property of fer- 
ments is to reinforee chemical changes in an indefinite amount of 
the substances upon which they act (catalysis). 
These results rather lead us to suppose, that this is a case of 
chemical action between “enterokinase” and zymogen, in stoechio- 
metrical proportions. 
If this supposition is right, then after a certain quantity of 
intestinal juice has been added sufficient to transform all the zymogen 
of a definite quantity of pancreatic juice into the enzyme, an addition 
of more intestinal juice would not only not increase the transfor- 
mation, but would have the opposite effect; because in that case the 
surplus of intestinal juice, which in itself does not digest white of 
egg, would act as a diluent. This in fact is the case. 
The name ‘enterokinase”, which corresponds with “lipase”, 
“maltase”’, etc. suggests a ferment and is therefore not appropriate. 
The name “zymolysine” appears to us to be preferable. 
We have already mentioned that the intestinal juice contains 
micro-organisms. The question arises whether these, or the products 
of their metabolism furnished the active substance. To answer the 
question whether the bacteria as such are responsible for the action, 
the intestinal juice was filtered through a Chamberland’s bougie 
and the experiments with the clear filtrate, were repeated. The 
results were the same; although the first filtrate showed a somewhat 
less powerful action than the unfiltered fluid, this was not the case 
with the last filtrate. This must be attributed to the circumstance, 
that the bougie retains active substances in the beginning of the 
filtration as was found by SamoïLow, in his experiments with 
solutions of pepsin and diphtheria-toxin. 
The bacteria as such are therefore not the active agents, but the 
question still remains whether their metabolic products have any 
such action. 
To investigate this the intestinal juice was again filtered through 
a Chamberland’s bougie and the filtrate boiled. By this process the 
active substance is destroyed. If this had formerly originated from 
bacteria, then, after bringing the same bacteria into the boiled liquid 
and heating to 38°, another culture was bound to produce the same 
products as before. But after the bacteria had full scope for deve- 
lopement in the previously boiled intestinal juice, the juice obtained 
in this manner, mixed with fresh pancreatic juice, did not show 
the slightest activity on white of egg. 
