170 BACTERIOLOGICAL DIAGNOSIS. 
cultures, unless the rigid antiseptic precautions are 
taken. Streptococci are common contaminations of 
cultures, but rarely occur in film specimens. 
3. Anthrax bacilliitThese may be detected with ease 
and certainty, but they are never found in the blood 
until it is too late to save the patient. 
4. Tubercle bactlh.—These are only present in very 
scanty numbers and are very difficult to detect. The 
diagnosis of miliary tuberculosis is to be made by other 
methods, chiefly by that of exclusion. 
5. The pueumococcus is found in severe cases of 
pneumonia (probably it might be found in most cases 
if a sufficiently large quantity of blood were examined) 
and in septicemia and ulcerative endocarditis when 
due to this organism. When found in the blood by 
ordinary methods it always indicates a bad prognosis 
and suggests the use of anti-pneumococcic serum. The 
identification of the organism is easy and certain if they 
are present in quantities sufficient for them to be found 
in films. 
6. Typhoid bacilli are present in the blood in all cases 
of typhoid fever, but their isolation is difficult and the 
diagnosis of the disease is made by other methods. 
7. The bacillus of glanders may be found in acute cases 
of that disease, but its isolation and identification are 
matters for an expert. 
8. The influenza bacillus is present in some, or, accord- 
ing to some authorities, all cases of influenza. It may 
be searched for in films, but no importance should be 
attached to a negative result. 
g. The bacillus of plague—This organism is often 
present in the blood in relatively large numbers, and 
the disease can usually be diagnosed after a careful 
search through a number of suitably stained films. But 
