358 COLLECTED STUDIES IN IMMUNITY. 



0.008 cc. poison solution No. 3, 

 0.2 cc. brain emulsion; 



one hour later! 

 Viooo antitoxin unit 



we not only found no excess of antitoxin, but found that the injec- 

 tion of such a mixture into mice caused death by tetanus." 



The result of this experiment led v. Behring to conclude that 

 further study of the poison-neutralizing power of guinea-pig brain 

 would probably decide the question in favor of Metchnikoff's views 

 as outlined above. A subsequent study from v. Behring's insti- 

 tute demonstrated that a union evidently takes place when living 

 brain and tetanus poison come together. 



Ransom 1 studied the conditions found in the subarachnoid space 

 after injections of tetanus poison or tetanus antitoxin. It would 

 lead us too far to recapitulate these brilliant experiments, and I 

 shall, therefore, content myself by quoting Ransom's conclusions 

 which are as follows: 



" These experiments strongly corroborate the assumption that 

 tetanus antitoxin is bound in the central nervous system; they also 

 indicate that this union takes place somewhat gradually." 



There is surely no objection to our placing these experiments 

 on the living brain parallel with those made on the dead brain. It 

 would be incomprehensible for a brain, removed at once from a 

 freshly killed animal, to be different in its property of binding tetanus 

 poison from what it was a few minutes previously in the living animal. 



1 had just begun a study in this institute dealing with these 

 problems, but discontinued them on the appearance of Ransom's 

 paper since that had so well covered the subject. 



Some time after this Kitashima's experiments were taken up by 

 Gruber, 2 although without re-examination. In these experiments 

 Gruber saw further proof of the incorrectness, according to him, of 

 Ehrlich's Side-chain Theory. In response to this, however, Paltauf 3 

 very aptly demonstrated that a simple calculation will show that 

 Kitashima's experiments cannot in any way be regarded as con- 

 clusive. He expressed himself as follows: 



J Hoppe-Seyler's Zeitschrift fur physiol. Chemie 1900-1901, Vol. XXXI, 

 p. 282 et seq. 



2 Munch, med. Wochensch. 1901, Nos. 46-49. 

 8 Wiener klin. Wochensch. 1901, No. 51. 



