CHAPTER II. 



THE DISTRIBUTION OF COMMA-BACILLI. 



IN the preceding account by Koch we see, then, that (a) 

 the comma-bacilli occur in the intestinal dejecta during the 

 acute stage of the disease : (b) the comma-bacilli are present 

 in the mucus-flakes and in the fluid of the contents of the 

 small intestine, chiefly and most numerously in the lower 

 portion of the ileum ; towards the upper part of the ileum 

 their number decreases, and in the jejunum they become 

 very scarce hence the vomit is as a rule free from them, 

 and when they are present it is no doubt owing to 

 regurgitation : (c) the comma-bacilli are present in the tissue 

 of the mucous membrane of the lower ileum, in the epi- 

 thelium of the surface, in the lymphatic tissue of the 

 mucosa, within the cavity of the crypts of Lieberkiihn as 

 well as between the epithelium lining these crypts and their 

 limiting membrana propria, but especially in the lymph- 

 follicles of the Peyer's patches ; these according to Koch 

 are in pure acute typical cases visible as swollen hypersemic 

 structures, the blood-vessels of the marginal portion being 

 distended and filled with blood, and hence strongly marked ; 

 in these blood-vessels Koch states that he found them in 

 great abundance : (d) the more acute and typical a case of 



