A quantity of blood was taken in citrate from dog Ko. 13 

 and from a control animal. Each lot was washed twice, using 

 175 volumes of salt solution. Samples from the resulting cells 

 were then separately incubated with Staph, aureus and B. typho - 

 sus. The results are civen in the table. 



Whether the energetic phagocj'-tosis of B. typhosus by the 

 washed cells of the immune animal, in the absence of serum can 

 be interpreted as the action of an immune cell, or whether there 

 was left upon the cell enough highly potent i.amune serum to op- 

 sonize only the specific bacteria is a matter to be decided by 

 more detailed observations. That the last explanation, however, 

 is probably the true one is suggested by Illein's (27) work on 

 the dilution of sera. 



A quantity of polymorjihonuclear leucocytes were recovered 

 from the urine of dog No. 13 and when incubated with sensitized 

 bacteria were actively phagocytic, as indicated in the follow- 

 in-' results. 



inimal providing serum. 



(30) 



