MYCOBACTEBIUM LEPK^E. 421 



gelatin stab the growth is scanty ; upon the surface a dry, 

 thin, wrinkled pellicle, with no liquefaction. Upon agar 

 just like the T. B. on glycerin-agar, only a little more 

 luxuriant and more thickly padded (62, v). Bouillon is 

 clear with a crusty pellicle. The growth on potato is 

 wrinkled, thick, sharply outlined, whitish-yellow. The 

 growth upon milk is strikingly different from all varieties 

 studied by us. It is not coagulated, and after one to three 

 months takes on a dark violet-gray color, the pigment being 

 soluble in alcohol. 



Mycobacterium tuberculosis S ranicola. L. and N. 



The efforts of various investigators to acclimate the T. B. 

 to the frog resulted in the information that also here the T. B. 

 is gradually transformed into a variety which grows at lower 

 temperatures. For details see Lubarsch (Z. H. xxxi, 187). 



Mycobacterium tuberculosis e anguicola. (Moeller.) 

 L. and N. 



Moeller, Therapeutische Monatshefte, Nov., 1898; Lu- 

 barsch (Z. H. xxxi, 187). 



Isolated from the spleen of a blindworm which was in- 

 fected one year previously with human tuberculosis 

 (sputum). Grows best at 22 (generally not at all at 28 

 to 37) ; upon agar it forms a moist, glistening white layer ! 

 In dilute bouillon and non-albuminous nutrient media 

 plentiful branching occurs. It cannot be inoculated into 

 rabbits. 



Mycobacterium leprae. (Armauer Hansen.) L. and N. 



(Plate 62, i-iv. ) 

 Common Name. Lepra bacillus. 



Principal Literature. Max Wolters, Der Bacillus leprae (C. B. xm, 

 469), and Finger in Ergebn. der allg. Aetiologie, 1896. Compare 

 also Mitteilungen und Verhandlungen der internation. Leprakonfer- 

 enz in Berlin, Oct., 1897, 2 Bande; Babes: Der Leprabacillus and die 

 Histologie der Lepra, Berlin, 1898. 



Since the communications of Armauer Hansen and 

 Neisser (Virch. Archiv, LXXXIV, 514) there has been no 

 doubt that the cause of leprosy is a non-motile organism, 



