450 APPLICATION OF METHODS OF BACTERIOLOGY 



and infiltrated to such an extent as often to interfere with 

 the use of the legs. In male animals the testicles become 

 enormously distended with pus, and on closer examination 

 a true orchitis and epididymitis are seen to be present. 

 The internal organs, particularly the lungs, kidneys, spleen, 

 and liver, are usually the seat of the nodular formations 

 characteristic of the disease. From all of these disease-foci 

 the bacillus causing them can be isolated in pure culture. 



Staining in Tissues. — ^Though always present in the diseased 

 tissues, considerable trouble is usually experienced in demon- 

 strating the bacteria by staining-methods. The difficulty is 

 due to the fact that the bacteria are very easily decolorized, 

 and in tissues stained by the ordinary processes are robbed 

 of their color even by the alcohol with which the tissue is 

 rinsed and dehydrated. If we will remember not to employ 

 concentrated stains, and not to expose the sections to the 

 stains for too long a time, but little treatment with decolor- 

 izing-agents is necessary, and very satisfactory preparations 

 will be obtained. A number of methods have been suggested 

 for staining the glanders bacilli in tissues, and if what has 

 been said will be borne in mind, no difficulty should be 

 experienced. Two satisfactory methods that we have used 

 for this purpose, though perhaps no better than some of the 

 others, are as follows: 



a. Transfer the sections from alcohol to distilled water. 

 This lessens the intensity with which the stain subsequently 

 takes hold of the tissues, by diminishing the activity of the 

 diffusion that would occur if they were placed from alcohol 

 into watery solutions of the dyes. Transfer from distilled 

 water to the slide, absorb all water with blotting-paper, 

 and stain with two or three drops of 



Carbol-fuchsin . . lO o.c. 



Distilled water . loO c.c. 



