440 BACTERIOLOGY. 
exist in only the most minute numbers. The Elsner 
method has the objection that it is very difficult to work 
with in hot weather. The Hiss plate medium has the 
objection that it is a difficult medium to prepare. If 
the acidity is not just right the thread outgrowths do 
not appear. Indeed, the only sure way is to test a new 
batch of medium with a pure culture and alter the 
reaction until the culture grows correctly. A very few 
varieties of the typhoid bacillus do not produce typical 
thread outgrowths from the colonies. 
The Capaldi medium has the objection that some of 
the typhoid and some of the colon colonies frequently 
look much alike. If one, however, will always pick 
out the colonies which look most like the typhoid, it 
will usually turn out that typhoid bacilli have been 
obtained if any were present. Personally, for general 
use I prefer the Capaldi medium for the plate cultures 
and the Hiss tube medium for identifying the bacilli 
obtained. Through these media we are now in a posi- 
tion to obtain and identify typhoid bacilli from feces, 
urine, etc., within forty-eight hours. 
Recently numerous investigations have been carried 
out to discover how frequently and at what period in 
typhoid fever cases bacilli were present in the feces 
and urine. In the laboratory Hiss has recently exam- 
ined the feces in forty-three consecutive cases, thirty- 
seven of which were in the febrile stage and six con- 
valescent. In a number of instances only one stool was 
examined, but even under these adverse conditions the 
average of positive results in the febrile stage was 66.6 
per cent. 
Out of 26 cases of typhoid fever in hospitals exam- 
ined, 21 were in the febrile stage and 5 convalescent. 
