IIo 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 Léffler’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. 
