36 MICROBES AND TOXINS 



this are made up of B. bifidus. The proportion is less (70%) 

 in the child receiving a fair quantity of animal food. 



In the human race three microbial species seem to be chiefly 

 capable of provoking the putrefaction of albuminous material 

 in the intestine ; namely the three anaerobes : B. putrificus of 

 Bienstock, B. sporogenes and the B. of Welch also called 

 B. perfringens. 



Not only are these three anaerobes putrefying organisms but 

 they seem also to be true pathogenic organisms. Putrificus 

 has been found in peritoneal suppuration, in appendicitis and in 

 various intestinal disorders. B. sporogenes has been found in 

 many cases of diarrhoea ; B. perfringens is common in acute 

 and chronic suppurations, and in infantile diarrhoea : it is also 

 the cause of crepitating gangrene or gaseous phlegmon. The 



FIG. 13. Bacillus FIG. 14. Welch's bacillus 



putrificus (Bienstock). (B. perfringens). 



study of their virulence and toxicity by experiments on small 

 laboratory animals and monkeys has hardly been begun. They 

 indicate well how delicate is the distinction between a simple 

 saprophyte of wide prevalence and a pathogenic organism 

 properly speaking. 



The B. coli, the commonest and most abundant bacterium 

 in the intestine, though it was considered by Schottelius, in his 

 experiments on the aseptic chick, as an indispensable adjunct 

 to nutrition and though it has even been employed as a remedy 

 for constipation, is nevertheless prejudicial to health. 



It does not, it is true, attack the genuine albumins but it 



