SIGNIFICANCE AND ORIGIN OF (DEFENSIVE) FERMENTS 89 



According to our observations, there is not the 

 slightest doubt that the animal organism is not left 

 without means of defence against disharmonious sub- 

 stances. If such products make their way into the 

 body, the latter sends out defensive ferments that are 

 directed against special kinds of substrates. Not only 

 do they effect the destruction of the specific character 

 of the parenterally introduced substance by means 

 of an extensive decomposition, but they render 

 possible the utilization of the products of the decom- 

 position in the general metabolism. The reaction 

 we have demonstrated enables us at any time to decide 

 whether a certain substance is in harmony with the 

 body or not. We have already emphasized the fact 

 that we must distinguish not only substances that are 

 in, or out of, harmony with the body, but also those 

 which are in, or out of, harmony with the blood or its 

 plasma, or again with the cells. We have already 

 described how the intestine, with its ferments and 

 those of its accessory glands, decomposes all dis- 

 harmonious substances until an indifferent mixture of 

 only the simplest units is left; and how then the cells 

 of the gut- walls, and of the liver, carefully test the 

 absorbed products for the absence, or transforma- 

 tion, of all substances that are out of harmony with 

 the body and blood. Moreover, all the cells of the 

 body take care that nothing shall pass from them 

 into the circulation which has not attained a certain 



