MYCOBACTERIUM LACTICOLA p PERRUGOSUM. 431 



Indol is formed in small amount and H 2 S in both* 

 sugar bouillon and ordinary bouillon. Acid production 

 is limited; in 10 c.c. of 2% grape-sugar bouillon as much 

 as corresponds to 0.6 c.c. of decinormal sodium hydroxid. 

 Gas is not formed in nutrient media containing sugar. 

 Gelatin is not liquefied. 



Distribution. Found in milk, butter, grass; see page 

 435. For pathogenesis, see page 434. 



We can separate the following from this only as a 

 variety : 



Mycobacterium lacticola ,3 perrugosum. L. and N. 



(Plate 63, i-vn.) 



Synonym. Butter organism of Rabinowitsch. We 

 obtained two cultures which corresponded perfectly. 



It is very similar to the Myc. lacticola a planum, and 

 perhaps only a cultural form of the same, for Rabino- 

 witsch described the young cultures as moist, thick, and 

 creamy when cultivated direct from the animal body, and 

 only after multiple passages through animals do they 

 acquire the dry, early wrinkled character which this form 

 presents. 



Regarding the microscopic character, nothing special is 

 to be said. We report, in detail, regarding the growths of 

 these forms because of the interest which they now possess. 



Glycerin-agar Plate. Microscopically in a short 

 time there appear much wrinkled, irregularly dentate, dry 

 scales, which later increase perceptibly in size. They are 

 transparent, grayish-white, and are easily lifted from the 

 surface and broken up (63, iv). When magnified sixty 

 times, the smallest and youngest colonies are very granu- 

 lar; being fringed and torn at the periphery, grayish-white 

 and transparent (63, in). Later they become opaque, 

 brown to gray, with irregularly distributed markings, 

 often spotted like a panther's skin (63, n). The gelatin 

 plates are scarcely different. 



Glycerin-agar Streak Culture. Similar to the growth 

 on the plates; there occurs here also an abundant, wrin- 

 kled, dry formation, which is extraordinarily like the 



