BOVINE TUBERCULOSIS 143 



water of condensation, a thin membrane which passes on to the walls ot 

 the tube. In old cultures the coating is frequently very much corru- 

 gated, and sometimes also exhibits a yellow, orange, or light-brown 

 colour. 



Bouillon or Glycerine Bouillon becomes clouded with a sediment, and 

 in forty-eight hours a membrane forms on the surface, which sinks very 

 easily to the bottom of the medium, if shaken, after which another 

 membrane forms, which passes up the sides of the tube. A slight 

 formation of indol was observed in bouillon cultures. 



On Potatoes the growth is rapid and plentiful, exhibiting a thick, 

 greyish, moist coating in twenty-four hours. 



Sterile Milk is not altered by the growth of the bacteria, but a 

 yellowish-white membrane forms on the surface. 



The morpho-biological characteristics above mentioned correspond 

 to those of the acid-resisting bacteria discovered by Rabinowitsch. 



Pathogenesis. These acid-resisting bacteria produced disease 

 processes in guinea-pigs when injected into the peritoneum. 



The liver was the only organ in which the lesions bore a distinct 

 resemblance to those of tuberculosis. The tubercles were of a greyish- 

 white colour, and penetrated from the surface of the liver into the 

 parenchyma, easily detached from the surrounding tissue. Small to 

 pinhead-sized yellow spotted foci were also observed on the surface 

 as well as in sections of the organs. The spleen, on the contrary, 

 never exhibited the appearance of a genuine tuberculous spleen. The 

 enlargement, dark colour, and characteristic marbling were awanting. 

 In the most of cases extensive peritoneal adhesions were present. 

 The mesenteric lymph-glands were not very much enlarged. In one 

 case softening was observed ; it was of a purulent nature, not caseous. 

 These bacteria frequently cause peritoneal lesions which exhibit a 

 decided tendency to recovery. In cases where reparative changes 

 were observed, the acid-resisting bacteria appeared to die and dis- 

 appear, because in cover-glass specimens and sections from some of 

 the guinea-pigs experimented with, the bacteria could no longer be 

 detected. Two chickens and one dog injected intraperitoneally with 

 a pure culture remained unaffected. According to Rabinowitsch, 

 rabbits are refractory. Injection into the anterior chamber of the 

 rabbit's eye caused inflammatory changes which did not persist very 

 long. 



HORMAN AND MORGENRATITS METHOD OF DEMON- 

 STRATING TUBERCLE BACILLI IN BUTTER. 



1. Inject 4 to 5 c.c. of butter melted at 37 C., and thoroughly mixed 

 into the peritoneal cavity of three guinea-pigs. (Allowing the butter to 



