290 BACILLI OF THE TYPHOID GROUP 



that he had discovered the cause of this disease, and named the micro- 

 organism Bacillus Neapolitanus. In the following year Escherich 

 demonstrated the bacillus in the stools of normal milk-fed infants, 

 and it has since been found as an entirely normal inhabitant in 

 the intestines of man and most of the domestic and wild animals. 

 It is, however, claimed that the bacillus does not occur in the intes- 

 tines of the horse. The organism is found widespread in nature as 

 a saprophyte. Some authors, like Fliigge, strongly maintain that the 

 organism is ubiquitous and occurs extensively in air, soil, water, and 

 independent of contamination from human feces or animal manure. 

 Escherich and Pfaundler, conceding its widespread prevalence in 

 the outside world, incline to the belief that it is generally, directly 

 or indirectly, derived from fecal matter. They admit, however, that 

 the bacillus has also been found in moderate numbers in water, which, 

 according to chemical analysis, was absolutely pure and unobjection- 

 able and showed no chemical evidence of contamination with sewage. 

 Weisenfeld, in 56 specimens of water, both good and bad, always found 

 the Bacillus coli, and claims, for this reason, that the presence of this 

 organism cannot be used as an index of contamination with sewage. 

 The same standpoint was previously taken by Kruse, Beckmann, 

 Pajal, Miquel, Schumann, and, as stated, by Fliigge. The question 

 has been here discussed because occasionally it becomes a matter of 

 dispute whether milk and other foods containing the colon bacillus 

 must be considered as contaminated with fecal matter or not. There 

 is no doubt that enormous numbers of the colon bacillus occur in the 

 intestines of cattle, as it is found in great numbers in the intestines of 

 man. In both man and animals the bacillus is ordinarily not patho- 

 genic, but in fact beneficial. It cannot split up and produce putre- 

 factive changes in native albumins, but it splits up carbohydrates 

 (starches and sugars). It is quite evident that it plays a physiologic 

 and beneficial part in the intestines and prevents excessive putrefactive 

 processes. While actual counts of the colon bacillus in the feces of 

 animals have not been made, it has been ascertained by Eberle and 

 Lange that 1500 to 3500 millions per gram of feces are present in the 

 stool of milk-fed healthy infants, and according to Sucksdorf 's estima- 

 tion the figure in adults is still 381,000,000 per gram. Ordinarily the 

 Bacillus coli, as stated, is not pathogenic, but it may, in consequence of 

 inflammatory processes, leave the lumen of the intestines and wander 

 through the damaged wall of the gut into the peritoneal cavity, the 

 bladder, the ovary, the kidneys, etc., producing either alone or in 

 combination with other bacteria serious pathologic conditions. 



Morphology and Staining Properties. The Bacillus coli is generally 

 a short, rather plump rod, 2 to 4 micra long (sometimes as long as 

 6 micra), and from 0.4 to 0.7 micron wide, with rounded ends. In 

 culture media and also in tissues which it has invaded in a patho- 

 genic manner it sometimes becomes very short, so that it resembles a 

 coccus. It occurs singly or in pairs, and in culture media also in longer 





