ORIGIN OF CYTASE. 319 



cocytes may be studied in stained microscopic sec- 

 tions of the organs (lungs). Leucocytes which 

 have undergone phagolysis are seen to be clumped 

 in the pulmonary vessels and in their immediate 

 vicinity one finds many micro-organisms which 

 have been changed into the characteristic granules 

 by the action of the cytase which has escaped from 

 adjacent leucocytes. Coincident with the phe- 

 nomenon of phagolysis, the leucocytes lose their 

 phagocytic power; hence, no bacteria are found 

 within the leucocytes. On the other hand, all 

 those vibrios which are remote from the leuco- 

 cytes have a perfectly normal appearance. Phago- 

 lysis in the blood stream may be prevented, just as 

 in the peritoneal cavity, by a preceding injection 

 of bouillon into the vessels. In this instance whes 

 the culture is injected no extracellular solution or 

 transformation of the organisms into granules? 

 takes place, but as in the peritoneal cavity, theit 

 destruction is accomplished entirely within the 

 microphages. Metchnikoff holds to the correct- 

 ness of these observations and interpretations, al- 

 though contradictory results were obtained by 

 Pfeiffer and his pupils. As further evidence that 

 cytase does not exist normally in the plasma Metch- 

 nikoff cites the condition which is found in the 

 anterior chamber of the eye in immune animals. 

 The vibrios continue unaffected in the aqueous 

 humor until such a time as leucocytes wander in, 

 when they are destroyed by phagocytosis. Hence, 

 cytase does not exist in the aqueous humor, and 

 if not in the aqueous humor it is surely absent 

 from the plasma; for if present in the plasma it 

 would reach the anterior chamber by a process of 



