JOHN W. CHURCHMAN 33 



influenced by physical disintegration of the cell wall something more than a chemical 

 process appears to be concerned. Perhaps degree of fineness of emulsification of the 

 acid fast constituent plays a part. 



MUCH GRANULES 



Acid fast organisms are also gram positive. But the two characteristics do not 

 necessarily appear at the same stage of bacterial development, and one of them may 

 be upset by processes which do not disturb the other. Krylow,' for example, showed 

 that very young tubercle bacilli stain neither by the method of Ziehl nor by that of 

 Gram, and that they become gram positive before they become acid fast; Wherry^ 

 showed that by growing on suitable media the organisms may be made to lose their 

 acid fastness while remaining gram positive ; and Aronson^ showed that the gram pos- 

 itivity of B. tuberculosis could be reversed by treatment with trichlor ethylene. 



In 1907 Much, in examining the tuberculous lesions of a group of animals which 

 had died of the disease, was unable to find organisms which stained by the method of 

 Ziehl but did find granular forms which stained by that of Gram.'' He concluded that 

 he was dealing with a cycle of B. tuberculosis other than the one usually encountered, 

 and stated that it appeared probable that the method of Ziehl stains substances of the 

 tubercle virus other than those stained by the method of Gram. It is therefore pos- 

 sible to obtain positive results with the method of Gram in cases in which examination 

 by the method of Ziehl is negative. His findings were as follows: (i) There is a gran- 

 ular form of tubercle virus not stainable by Ziehl. (2) This granular form is virulent. 

 (3) It occurs in tuberculous organs either as the only stainable manifestation of the 

 etiological factor of the disease or in company with a fine rod which is also not stain- 

 able by Ziehl. 



Krylow,' in reviewing Much's findings, came to the conclusion that gram positive 

 material appears in B. tuberculosis much earlier than acid fast material, and this ma- 

 terial tends to concentrate in granules. Acid fast material, on the other hand, is 

 spread diffusely throughout the bacterial body. Hence in young cultures a modified 

 method of Gram will demonstrate the Much granules. 



The significance of the Much granules is open to debate. Much's findings have 

 been repeatedly confirmed, and there seems little doubt that the bodies he described 

 are actually to be found in many tuberculous lesions. They may, however, be de- 

 generation products (Rosenblat). In any event, demonstration of their presence is 

 almost without diagnostic value since other bacilli form granules of similar appear- 

 ance. 



STAINING ELEMENTS 01" BACTERIAL STRUCTURE 



Certain structural portions of some types of bacteria may, under certain condi- 

 tions of growth, be demonstrable by suitable methods of staining. Here belong the 

 spore, the capsule, flagella, polar bodies, metachromatic granules (the Babes-Ernst 



'Krylow, D. O.: loc. cil. 



^^ Wherry, W. B.: loc. cit. 



3 Aronson, H.: Berl. klin. Wchnschr., 35, 484. 1898; 47, 1617. 1910. 



''Much, H.: Bcilr. z. Klin. d. Tuberk., 8, 85. 1907. 



