365 



YI. — Tlie Llfe-liistory of the Menuigococcus. 

 By Edward C. Hort, F.R.C.P. Ed. 



(Read April 18, 1917.) 

 Plates XXIV and XXV. 



In November of last year I enjoyed the privilege of demonstrating 

 to this Society, with the aid of Mr. Martin Duncan's micro- 

 photographic skill, some morphological phases in the life-histor}^ 

 of certain bacteria, such as the Bacillus c.vanthematicus of typhus 

 fever, and the organisms of the enteric group. 



You will .perhaps remember that the object of my demonstra- 

 tion was to present evidence, admittedly incomplete, that the lower 

 bacteria are not necessarily what they seem to be, and as we are 

 taught, namely, unicellular organisms with a simple life-history. So 

 far, indeed, from their life-cycle being a simple affair, beginning 

 and ending with transverse binary fission into two equal parts, the 

 evidence, such as it was, suggested that the life-history of bacteria 

 is one of great complexity, and includes, in some cases at least, a 

 minute filterable, and invisible, or almost invisible, stage. 



To advance such a doctrine as this in the face ot up-to-date 

 bacteriological teaching is to proclaim oneself a heretic, and to 

 invite the doom that awaits all heretics. 



As, however, I have not yet been led to the stake, I venture to 

 ask you once again to examine very briefly, as you did last 

 November, the articles of faith of the orthodox bacteriologist, who 



EXPLANATION OP PLATES XXIV. and XXV. 



Fias. 

 1.— Meningococcus. Case 4. Cerebro-spinal fluid incubated two nights, then 



on serum-agar one night. Benian's Congo-red film. X 1500. 

 2. -Case 3. Plymouth. Cerebro-sinnal fluid incubated two nights, then placed 



in acid broth two nights ; then in serum-broth one night, x 1500. 

 3, 4. — Meningococcus. One colony, on serum-agar from incubated cerebro-spinal 



fluid containing budding "cysts and meningococci. Fermenting glucose 



only. Spread on serum-agar. Confluent growth A.S.B. x 60 to Phen ; 



then incubated five days. Centrifuged, and examined in Congo-red. 



x 1500. 

 5. — Case 3. Plymouth. Cerebro-spinal fluid incubated two nights, then placed 



in acid broth two nights. X 1500. 

 6. — Case 3. Plymouth. Cerebro-spinal fluid incubated two nights, then placed 



in acid broth two nights ; then in serum broth one night, x 1500. 

 7, 8. — Meningococcus. Serum broth. Benian's Congo-red fibn. x 1650. 



