390 BACTERIA IN INFECTIOUS DISEASES. 



admit that there are cases, recognized by expert 

 pathologists as undoubtedly tubercular, in which 

 no bacilli can be found in tubercles obtained from 

 the lungs post mortem. Thus Prudden, of New 

 York, while recording the fact that he has, in a 

 considerable number of cases of acute and chronic 

 phthisis, found, almost invariably, the bacillus of 

 Koch " in and about all of the cavities, in many 

 of the larger areas of coagulative necrosis, and in 

 a considerable proportion of the miliary tuber- 

 cles;" yet reports two cases which form an ex- 

 ception to this rule. In one, an abundance of 

 miliary tubercles covered the lateral surfaces of 

 both lobes of the left lung; "most of these were 

 of the usual giant-celled and epithelioid-celled 

 type, with a more or less well-marked reticulum. 

 In none of those examined was there well-marked 

 cheesy degeneration. Six hundred and ninety-five 

 sections, about .01 millimeter in thickness, were 

 made from ninety-nine different tubercles from 

 various parts of the tuberculous membrane, and 

 stained in the usual manner by Ehrlich's method 

 in several different lots. In not one of these six 

 hundred and ninety-five sections could a single 

 tubercle bacillus be detected, although all were 

 examined with the most scrupulous care." In 

 another case, " nine hundred and nine sections 

 from a large number of peritoneal tubercles, from 

 different parts of the affected surfaces, stained by 

 Klirlich's method, revealed, under the most search- 

 ing scrutiny, no tubercle bacilli." In the same 



