96 BIOLOGY OF PNEUMOCOCCUS 



Weiss, 1509 who obtained an analogous reaction in rabbits. He saw 

 no parallelism between the toxicity and hemolytic power of the 

 extracts, nor any neutralizing action by antipneumococcic se- 

 rum. Weiss, like Rosenow, found a similar toxic principle in lung 

 exudates of patients suffering from acute lobar pneumonia. 

 Clough's 241 paper (1915) contained similar observations. In the 

 same year, Boehncke and Mouriz-Riesgo 134 failed to isolate the 

 toxic substance from young cultures or from sodium taurocholate 

 solutions of virulent strains. Contrary to earlier reports, these two 

 authors found that the serum of rabbits treated with these prepa- 

 rations displayed antitoxic action but did not affect the infective 

 process. There followed a paper by Weiss 1509 on "Pneumotoxin," 

 in which he repeated Cole's observations on the anaphylactoid re- 

 action caused by sodium choleate solutions of living, virulent, 

 washed pneumococci. The description of the properties of the 

 preparations agrees with previous accounts of the characters of 

 pneumococcal hemotoxin. 



Chesney and Hodges 221 departed from the idea that the intoxi- 

 cation in pneumonia was due to a toxin, believing that it was more 

 reasonable to associate the phenomenon with the growth of the 

 organisms, rather than with their death and dissolution. The au- 

 thors' attempts to detect toxic substances in fluid cultures of pneu- 

 mococci during the period of active growth proved entirely nega- 

 tive. 



The demonstration of a toxin was claimed by Olson 1029 who ex- 

 perimented with sterile sodium ricinoleate solutions of pneumo- 

 cocci. He also claimed that the intraperitoneal injection of such 

 preparations produced cutaneous reactions in animals and caused 

 clinical and pathological symptoms of pneumonia. An antiserum 

 against this substance appeared to prevent to a high degree both 

 pulmonary and cutaneous reactions. Olson stated without qualifi- 

 cations that a toxin had been demonstrated, that the action of the 

 immune serum was antitoxic, and that "indications are that the 

 toxin may be of value in the production of active immunity to 



