218 On the Presence of Hcem-agglutinins, etc., in the Blood. 



because so many red cells which have been engulfed by the leucocytes are 

 ghosts and, no doubt, have been too severely haeniolysed to be recognisable. 



In the concluding remarks in the preliminary paper on hoem-opsonins, it 

 was stated that " The experiments referred to in this communication entirely 

 agree with the observations of Barratt and Keith, conducted with the blood 

 sera and cells from the lower animals. There was nothing to show that the 

 agglutination, opsonic, or hgemolysing properties of normal or immune sera on 

 red blood corpuscles have any direct relation to one another." 



From the investigations which have been made for this report, some of 

 which have been referred to, it has been noted that a serum may hsemolyse, 

 agglutinate, and incite phagocytosis of certain red cells, but although it 

 may be capable of agglutinating and haemolysing certain red cells, yet the 

 degree of phagocytosis which is present may be negligible, or phagocytosis may 

 be present without the other phenomena ; on the other hand, a serum which 

 has a high agglutinative value is more likely to give a somewhat similar 

 incitor reaction than otherwise, although not necessarily. 



I have again to thank Mr. H. A. F. "Wilson for his invaluable assistance, 

 and also Dr. Athole Ross and Mr. Irvine, all co-workers in my laboratories. 



