LEPROSY 153 



clear, rather thick rods. If a drop of aqueous methyl- 

 violet be now added, the leprosy bacilli alone are stained. 



The grouping of the bacilli together in clumps and 

 masses is also a differentiating characteristic of the bacilli 

 in tissues, and does not resemble in any way the arrange- 

 ment of tubercular bacilli in giant-cells. 



The distribution of the leprosy bacillus within the body 

 is now known to be general in most of the tissues and 

 viscera, though it occurs more in the liver and spleen than 

 in the kidneys and brain. Kobner is the only pathologist 

 who claims to have found it in the blood. The bacilli are 

 found in cutaneous and other tubercles, and in the dis- 

 charges therefrom. 



Leprologists almost universally agree that the direct 

 implantation of leprous material upon solid nutrient media 

 gives negative results. Bordoni-Uffreduzzi claims, however, 

 to have cultivated the bacillus on peptone-glycerine-serum, 

 at a temperature of 35° to 37° C, on which it forms ' a 

 light yellow stripe with irregular edges along the needle 

 track.' The serum is never liquefied, and no growth ever 

 occurs in the condensation water. On glycerine-agar 

 plates, both on the surface and deeply in the medium, 

 colonies may be seen with a power of 100 diameters which 

 are gray net-like growths with irregular edges.* 



Bordoni-Uffreduzzi found that the organism grew only 

 with diflSculty at blood-heat on the serum, but after re- 

 peated subculture appeared to adapt itself more readily to 

 a saprophytic condition of life, and finally could be sub- 

 cultured on the gelatine. The inoculation of leprotic 

 culture into animals seems to produce no effect at all, 

 which would differentiate it from tubercle, and also appears 

 to indicate that leprosy is exclusively a human disease. It 

 is unknown how the bacillus is conveyed : and the causa 

 * Leprosy Commission Beport, p. 425. 



