436 ACTINOMYCETES. 



To cultivate the organisms from grass, the grass is cov- 

 ered with water (Phleum pratense is especially recom- 

 mended) and allowed to remain at 37° for tMrteen to 

 twenty-four hours. When frequent (every two hours) 

 examinations have demonstrated that acid-proof organ- 

 isms are present in quantity, plates are prepared. 



It cannot be stated with certainty whether these new 

 varieties of mycobacteria may also be pathogenic for man. 

 So far as we know, no acid-proof organisms which grow 

 upon all nutrient media and at room temperature have 

 been cultivated from the sputum in cases of pulmonary 

 diseases or from human organs. 



Ginsberg stained numerous bacteria from two cases of 

 eye disease, which were closely related to the T. B., but 

 they were not cultivated (C. B. xxii, 62). 



Flexner described a Streptothrix pseudotuberculosa Fl. 

 from the lung of an old negro, growing with beautiful 

 branching, staining by Gram's method, but imperfectly 

 acid-proof with the T. B. stain, and not certainly patho- 

 genic for guinea-pigs (Jour, of Exp. Med., iii, 435). 



Differential Diagnosis of the Mycobact. tuberculosis 

 (Tubercle Bacillus; T. B.)- 



1. If the T. B. is to be distinguished from bacteria 

 which are not acid-proof, simple preparations are stained 

 by the Ziehl-Neelsen method. Those which do not stain 

 can be left out of question. T. B. which do not stain by 

 the Ziehl-Neelsen method are unknown. - 



In the examination of sputum one proceeds as follows: 

 The sputum is to be obtained as free as possible from 

 foods and secretions from the mouth, and it is best col- 

 lected in a sterile dish after the mouth has been well 

 washed with water. Of the sputum, the more purulent 

 (not mucous) portions, which are in lumps, are selected, 

 spread upon the cover-glass, and stained (see Technical 

 Appendix). 



If no bacilli are found in a few preparations, although 

 tuberculosis is suspected of being present, then one of the 

 more searching methods described in the Technical Appen- 

 dix must be employed in the attempt to discover isolated 

 bacteria. 



