110 BACTERIOLOGICAL DIAGNOSIS. 



not much longer than the bacillus of influenza. It is 

 rather thick in proportion to its length, its length being 

 only about three times its breadth. It does not stain 

 by Gram's method ; it stains, indeed, with some diffi- 

 culty, and powerful stains (such as dilute carbol-fuchsin 

 or Loffler's blue) should be used. It is best demon- 

 strated in films made from the deeper parts of a typical 

 soft sore, for the superficial parts contain bacteria of all 

 sorts, and the recognition of Unna's bacillus is not easy 

 unless it is obtained in large numbers. 



The bacteriological examination for this bacillus has 

 most often to be made in cases of urethral sore or of a 

 sore concealed beneath a phimosis. The method of 

 obtaining the specimen is the same in both cases. A 

 fairly stiff platinum loop is inserted beneath the prepuce 

 or into the urethra, and moved gently about until the 

 most tender spot is found. This should be scraped as 

 forcibly as the patient will allow, and the loop with- 

 drawn, care being taken that the mass of secretion is 

 not wiped off in so doing. Several films should then be 

 made, the secretion being rubbed up on the slide with a 

 drop of water. They should be stained with either of 

 the stains mentioned above for five minutes or more ; it 

 is an advantage to warm them gently. They are then 

 rinsed in water, dried, and mounted, and examined 

 thoroughly with an oil-immersion lens. 



When buboes occur in the course of soft sore the pus 

 they contain should be examined for this organism as 

 soon as they are opened ; the interest in this is chiefly 

 scientific, for opinions are divided as to whether they 

 are caused by this germ or by pyogenic bacteria. In 

 three cases examined by the author, it was found (in 

 very scanty numbers) on one occasion, staphylococci on 

 another, and no bacteria of any sort in the third. 



