PROTEIN AND CIRCULATION 61 



coagulability, which is not, however, identical with 

 these substances. By waters has concluded that this 

 body is a substance called by him sero-mucoid. In spite 

 of these views Bergmann and Langstein and Kraus 

 assert that small amounts of true proteose are present 

 constantly. After feeding elastin Borchardt claimed to 

 find elastin proteose in the blood stream. Upon repe- 

 tition of this work of Borchardt, Abderhalden and 

 Ruehl failed to give it confirmation. The explanation 

 of Abderhalden and Oppenheimer that imperfect sepa- 

 ration of coagulable protein is responsible for the 

 proteose test was denied by Freund who maintained 

 that the method employed by Abderhalden not only 

 precipitated the coagulable protein but the proteose 

 also. 



From the foregoing brief review of only a few of the 

 investigations carried through for the decision of the 

 problem it is apparent that the whole question is in a 

 chaotic state of contradictions and that a positive 

 answer cannot be given. It may at least be said that 

 positive proof of the presence of proteoses and pep- 

 tones is still lacking. Perhaps one of the most con- 

 vincing arguments against the existence in the blood of 

 proteoses and peptones is derived from the work of 

 Abderhalden and Pincussohn. They have demon- 

 strated that just as with the parenteral introduction 

 into the body of native protein so with proteose injec- 

 tion there is a development in the blood plasma of an 

 enzyme capable of causing its disintegration to smaller 

 molecules. Such an enzyme is not present in the 



