t4 QUATERCENTENARY STUDIES IN PATHOLOGY 



the production of immunity against bacillus pyocyaneus. The methods 

 employed in different animals comprised : — 



1. Immunisation with increasing doses of pyocyanic filtrates. 



2. ti II toluolised broth cultures. 



3. »i M heated cultures. 



4. ti M heated cultures followed by 



living cultures. 



5. II II autolysed cultures (Neisser's 



and Conradi's methods). 



The general result of these experiments, several of which were 

 performed in each series, has shown that the immunity acquired is never 

 of a very high degree. In this respect my results differ from those 

 of Wassermann. Even in animals which have been apparently solidly 

 immunised over a considerable period with toluolised cultures, death 

 ensued acutely when about 3 - 4 lethal doses of the living culture were 

 injected into the peritoneal cavity. A few of the immunisation 

 experiments will sufifice to make this apparent. 



Experiment i. 



1904. 

 Nov. 8. — Rabbit's serum tested — no agglutination effect on B. Pyocyaneus, in 



dilution of i m 2. 

 Nov. 8. — Rabbit inoculated with 8 c.c. autolysed filtrate (Conradi). 

 Nov. II. — Serum agglutinated bacilli in 5 min., in dilutions from i in 4 — i : 100. 

 Nov. 14. — Agglutination complete i in 800. 

 Nov. 21. — 15 c.c. autolysed filtrate inoculated. 

 Nov. 27. — Agglutination complete i in 1700. 

 Dec. 29.— 20 c.c. autolysed filtrate inoculated. 

 Dec. 30. — Animal seriously affected. 



1905. 

 Jan. 4. — Agglutination i in 2000. 



Jan. 14. — Animal showed paresis of hind limbs and emaciation. 

 Jan. 20. — Animal died ; complete paraplegia, marasmus, (maladie pyocyanique 

 of Charrin). Post mortem — Parenchymatous degeneration of 

 kidney. 



(170) 



