FORMATION OF DEFENSIVE FERMENTS 65 



succeeded in supplying definite proofs for such a 

 view. It is onfly recently that experiments have 

 been made, by means of injections of peptones and 

 derivatives of amino-acids, especially of amines, 

 with a view to producing phenomena resembling 

 those of an anaphy lactic shock. It is difficult to 

 decide with any certainty what part is played, by the 

 ferments we have observed, in the setting up of 

 anaphylaxy. Several facts run counter to the suppo- 

 sition of a direct relation between the presence of 

 active ferments and the particular substrate against 

 which thev are directed. It has been proved, beyond 

 doubt, that these ferments exist in the blood at a time 

 when the anaphylactic shock cannot yet be produced 

 by a second injection of the same material as was used 

 in the first case. Further, it has already been pointed 

 out that these ferments are specific only in respect of 

 the group of substances which are used for th'e in- 

 jection, but not for the particular body that has been 

 introduced. To produce the shock, on the contrary, 

 the substrate, with which the animal under experiment 

 was rendered sensitive, must be present. A certain 

 importance, in regard to the setting up of the state 

 of shock, may be attached to the power possessed by 

 the plasma of decomposing albumen ; as is shown by 

 an observation which was made by Hermann Pfeiffer 

 and confirmed by ourselves, according to which the 

 proteolysis in the plasma disappears during the 



