ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 851 



at his own laboratory. His conclusions are, that the comma bacillus 

 was present, and generally in large numbers, in all the cases of cholera 

 which were examined ; that he has never met with the comma bacillus 

 except in cholera, and that the other curved bacilli described (Finkler 

 and Prior's, Lewis's, and Denike's or Fliigge's), differ from it in 

 important particulars. 



Mr. Cbeyne also combats Klein's arguments against the specific 

 nature of the comma bacillus. 



Dr. E. Van Ermengem has also published an elaborate report * to 

 the Belgian Minister of the Interior, which is the most exhaustive 

 that has yet appeared. He supports Koch's assertions. 



Etiology of Tuberculosis.! — Dr. E. Koch sums up the results 

 on this subject obtained by himself and others, adding some new 

 observations. 



The best mode of detecting the bacillus of tuberculosis is by the 

 staining reaction with anilin according to the methods of Ehrlich 

 and Rindfleisch. There is no other kind of bacterium with which it 

 agrees in this respect except the lepra-bacilli, and from them it is 

 distinguished by not taking up Weigert's nuclear-staining. The 

 variability in the behaviour of this bacillus with staining reagents 

 Dr. Koch believes to result from its being surrounded by a very thin 

 envelope. 



The separate individuals of the bacillus of tuberculosis are long 

 very narrow rods, with no segmentation of any kind, but often with 

 slight angles and curvings, and a tendency to spiral twisting, by 

 which they are distinguished from many other bacilli otherwise 

 resembling them in form, such as those of the septicaemia of mice. 



They occur within the cells of the tubercular nodules ; only in 

 small numbers in the cheesy substance. The formation of spores is 

 very frequent. When spores are about to be formed, the bacillus 

 does not break up into separate segments, but from two to six ovate 

 spores are formed in each, distinguished by their high refractive 

 power. 



Dr. Koch found the bacillus in the bodies after death of patients 

 who had suffered from every kind of tubercular disease; and in 

 especially large numbers in the sputum, where the formation of 

 spores is particularly abundant, and where it retains its vitality for 

 an extraordinary period. It occurs also in the excreta both of men 

 and animals suffering from tubercular disease. 



The culture of the bacillus of tuberculosis was carried out success- 

 fully on the solidified serum of the blood of oxen at a temperature of 

 37'-' C. The following are mentioned as special characters under 

 cultivation: — (1) It does not cause the serum to deliquesce; (2) it 

 sprcadH itself over the surface, lying loose upon it ; (3) the individuals 

 attach themKclves to one another in large masses, which fall to the 



• Ermeiifrcrn, E. van, ' Rechcrches eur Ic Microbe du Cholera Asiatiquo,' 

 Me'rn. Hw. I}.1kc Micr., x. (IHM) pp. 1-342 (13 pis.). 



t M T. K. iJoifhsgCBUDdheitHamtc, Berlin, ii. (1884) pp. 1-88 (10 pis.). Sco 

 Bot. tk,ntruli;l., xxi. (1885) p. 235. Cf. this Journal, ii. (1882) p. 385 ; iv. (1884) 

 p. 787. V ^f V >- 



