304 Chapter X 



of broth or physiological saline solution the day before, prevents the 

 production of Pfeiffer's phenomenon, in spite of the protective serum, 

 just as in vaccinated guinea-pigs. In both cases the vibrios, without 

 being transformed into granules by the fluid part of the peritoneal 

 exudation, are ingested by the phagocytes en masse and with extra- 

 ordinary rapidity. This experiment was repeated by Gamier 1 with the 

 typhoid cocco-bacillus. He first injected into the peritoneal cavity 

 of young guinea-pigs several c.c. of physiological salt solution, of fresh 

 broth or of some other fluid. The next day he introduced into the 

 same situation typhoid cocco-bacilli mixed with blood serum from 

 a donkey that had been for a long time immunised against this 

 organism. A few minutes (2 4) after this latter injection the leuco- 

 cytes, whose phagolysis had been prevented by the previous day's 

 preparation, were found crammed with cocco-bacilli. Some of these 

 bacilli, like those still free in the peritoneal fluid, retained their normal 

 form, but a very large number of those ingested by the microphages 

 were already transformed into granules. This experiment affords 

 fresh confirmation of the hypothesis that the substance which trans- 

 forms the cocco-bacilli or the vibrios into granules is the microcytase. 

 In the phagocytes in their normal condition this microcytase is found 

 in the microphages, but during phagolysis a portion of it escapes into 

 the surrounding fluid. In the control experiments made by Gamier 

 with young normal guinea-pigs not prepared by preliminary injection, 

 the simultaneous injection of typhoid cocco-bacilli and specific donkey's 

 serum set up this attenuated and not very typical Pfeiffer's phenomenon 

 described in Pfeiffer and Kolle's memoir. 



Soon after the discovery of Pfeiffer's phenomenon I 2 was able 

 to bring forward a proof that it was produced neither in the sub- 

 [320] cutaneous tissue, in the oedemas set up by the arrest of the circulation, 

 nor in the anterior chamber of the eye of animals when cholera vibrios 

 mixed with anti-infective specific serum were injected into these 

 situations. Here the micro-organisms retain their normal form, 

 remain quite alive and in this condition are ingested by the leuco- 

 cytes which are brought up to the points invaded. These cells, 

 attracted by the vibrionic products, do not undergo any phagolysis 

 and, untrammelled, fulfil their phagocytic function. Inside them are 

 found vibrios which have kept their elongated form and others which 

 have become transformed into granules. The exudations containing 



1 Ann. de Vlnst. Pasteur, Paris, 1897, t. xi, p. 773. 



2 Ann. de Vlnst. Pasteur, Paris, 1895, t. ix, p. 453. 



