320 INFECTION AND IMMUNITY. 



diffusion. Similar conditions prevail in edematous 

 fluids. In another instance a portion of a vein, 

 filled with blood, was resected and centrifugated 

 without the formation of a clot (absence of pha- 

 golysis) ; the plasma contained no cytase. Also 

 Gengou collected and centrifugated blood in tubes 

 which were coated with paraffin, and thus avoided 

 clotting; here also cytase was absent from the 

 plasma. 



increase of It would seem, then, that two important anti- 

 bacterial factors characterize immunity to cholera 

 power. an( ^ s j m j} ar infections : the development of specific 

 fixators, and a greatly increased phagocytic power 

 on the part of the leucocytes. Metchnikoff leans 

 to the view that bacteria, having absorbed fixators, 

 are more readily phagocytized, but no clear idea is 

 given as to the change which the fixators produce. 

 However, he. would not refer the increased phago- 

 cytic power entirely to the influence of the fixa- 

 tors. He believes that the leucocytes of the im- 

 mune animal have per se a higher phagocytic 

 power than that of the normal animal. In anthrax, 

 for example, the phagocytic power is height- 

 ened in spite of the fact that there is no increase 

 in specific fixators. This view, however, is op- 

 posed by Denys and Leclef, who found that the 

 leucocytes of the immune animal, when trans- 

 ferred to normal serum, had no greater phago- 

 c} r tic power than normal leucoc} ) 'tes. 



Metchnikoff believes that fixators, like cytase, 

 are produced by the microphage. That the lymph- 

 oid organs may form certain fixators seems prob- 

 able from the observations of Pfeiffer and Marx 

 in regard to cholera and Wassermann and Takaki 



