SYNOPSIS XV 



pigment formation. The meningococcus and M. catarrhalis — morpho- 

 logy — fermenting properties — pathogenesis — mixed infection — habitat. The 

 menivgococeus and the pneumococcus — symptoms produced — common com- 

 plications — seasonal prevalence — age incidence and mortality— distribution. 

 Such transition less credible than it appears — but not less credible than 

 instances known to occur— saprophytic and parasitic types of pneumococcus. 

 Conclusions. (107—115) 



CHAPTER IX 



SUPPOSED INSTANCES OP TRANSMUTATION BROUGHT 

 ABOUT EXPERIMENTALLY 



I. Major Horrocks's experiments {Journal of R.A.M.C. Vol. xvi). 

 Importance of the claims made by him. Criticism. Possibilities to be 

 considered — purity of original strain, peritoneum possibly not sterile, 

 possible contamination from skin, possible invasion from gut before or after 

 death, continuity of strain not confirmed by reversion or presence of 

 intermediate forms, different results obtained on repeating experiments, 

 results possibly explained by variation. Criticism. Conclusions. 



II. Relationship between paratyphoid organisms. 



A. Schmitts experiments. Experiment I. "Pliigge" type given to calf 

 in food, injected beneath skin — second strain isolated from blood. Experi- 

 ment II. Second strain injected into nasopharynx of second calf — third 

 strain isolated from blood and injected into vein, fourth strain recovered 

 after death — later strains resembled B. Gaertner in agglutination. Possible 

 fallacies, (a) contamination in original strain ? (6) contamination in bodies 

 of calves ? — not absolutely excluded by agglutination tests — B. Gaertner in 

 intestines of healthy calves, possible increase in numbers and virulence due 

 to local inflammation, might lead to systemic invasion, (cf. saprophytes, in 

 inflamed uterus) and fresh agglutination reactions of blood serum. 



. Experiments of MUhlens, Dahm and Fiirst. Mice fed on infected 

 meat — faeces of some contained B. Aertryck, of others B. Gaertner — due 

 to transmutation ? Possible fallacies, (a) contamination of original source ? 

 (6) contamination in bodies of mice ? — control — B. Aertryck in healthy 

 mice, presence possibly overlooked ?— their appearance favoured by in- 

 flammation and disturbed function of bowel. 



C. The Author's experiments. Experiment I. Guineapigs given B. 

 Gaertner in food — B. Gaertner and B. Aertryck isolated from faeces at 

 different times — control — two organisms transmutable ? — intestinal bacteria 

 undetected if few in number — disturbed function of bowel reveals their 

 presence — multiply in inflamed intestine (cf . B. coli in cholera) — such factors 

 may explain result of experiment — qualification — proof that in disordered 

 intestine unsuspected organisms make their appearance. Experiment II. 

 Faeces of six guineapigs examined — B. proteiu found in one case — guinea- 



