The Role of the Phagocyte in Cerebrospinal Meningitis. 435 



cells, fail to get digested. At the end of 15 minutes' incubation, the 

 aggregations are very large, and the germs cannot be acted on by the 

 normal saline. Living germs can, therefore, be demonstrated both within 

 and without the leucocytes after two hours' incubation in normal saline. 



In regard to mixture " D," the same explanation would apply. 



Finally we would like to draw attention to the fact that in some cases of 

 cerebro-spinal fever, the leucocytes of freshly drawn spinal fluid frequently 

 show the meningococci growing out from them in large numbers. The germs 

 can be seen filling the interior of the cells and actually bursting them open in 

 places and growing forth in dense masses. 



In one case under our care, " Hayes," this condition was very obvious. In 

 fig. 8 is shown a microphotograph of some of the freshly drawn leucocytes of 

 this case. In the centre of the figure is a large polymorph cell which has 

 been burst open on one side by a dense mass of meningococci. A close 

 examination of the fluid showed that almost every second cell w T as in a similar 

 condition. Staining with trypan blue showed at the same time that relatively 

 few of these cells were dead. It is clear that in instances like th§se the 

 meningococci are plainly alive within the leucocytes. 



Having now shown that the meningococcus can be alive within the 

 leucocytes, the suggestion that the disease appears as the result of acci- 

 dental carriage of the organism into the spinal canal by emigrating leuco- 

 cytes assumes 'some credibility. Should this suggestion prove true, then in 

 it we have an explanation of the fact that the disease is so seldom 

 transmitted direct, but usually through the intervention of a i: carrier." 

 Ingestion of the germs by the phagocytes would have to be an essential 

 factor in the propagation of the disease. As we have seen, the meningo- 

 coccus when freshly isolated, is insusceptible of being ingested by the 

 phagocytes in the presence of normal serum. 



It is also true of the meningococcus when isolated from the naso- 

 pharynx of a patient suffering .from the disease in the early stage. In a 

 recent case, where the organism was present in the naso-pharynx on the 

 third day of the disease, a very thick emulsion of the germ was incubated 

 with normal serum and washed leucocytes for a quarter of an hour at 

 37° C, and no trace of ingestion of the germ by the phagocytes could be 

 observed. 



At various times a considerable number of strains have been examined in 

 this connection, and although they gave rather variable results in certain 

 instances, on the whole we found that the further removed an organism 

 is from the case in which it caused the disease, either in point of time or 

 passage from throat to throat, the more susceptible does it become to 



