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NON-FLAGELLATE TYPHOID BACILLI 
By J. W. W. STEPHENS, M.D., Cantab., D.P.H. 
WALTER MYERS LECTURER IN TROPICAL MEDICINE, UNIVERSITY OF LIVERPOOL 
IN an article in the Thompson Yates Laboratories Report, 1903, I described a method of 
staining flagella with silver. Shortly afterwards I proceeded to demonstrate the 
method to a class of students, and to my great surprise and annoyance I failed 
to show any flagella at all in the culture of typhoid bacilli used. I made many 
attempts, but all were negative, and I naturally concluded that there must have been 
some factor at work in my earlier successes which I was now unable to repeat. I 
feared, too, that I had given publicity to a method which was uncertain, since I 
myself was now unable to get positive results. I then set about discovering what 
procedure in my previous method had escaped me, and 1 made a large series of 
tedious experiments extending over many months in attempting to determine 
exactly in what respect my method was now wrong. But all to no purpose, I failed 
to stain a single flagellum. The suspicion then gradually arose in my mind that the 
culture might be to blame. I consequently stained three different laboratory cultures 
of typhoid, but again all were negative with regard to flagella. I then felt that the 
culture was not to blame but the method, and I once more applied myself to 
repeating my original method and to making all kinds of modifications, but again 
with negative results. It then occurred to me to examine my cultures (fresh) in 
the hanging drop, and to my surprise I found that none of them exhibited the 
typical motility of typhoid bacilli, but they only showed ' trembling ' movements. I 
was not aware at the time that typhoid bacilli could become practically non-motile, 
but on consulting the literature I found that this was recognized. I could find no 
statement, however, that this ' non-motility ' was associated with loss of flagella, and 
it appeared to me now possible that my numerous failures were due not to a faulty 
method but to the fact that the bacilli had really no flagella. I consequently procured 
a freshly isolated typhoid bacillus which showed active motility, and proceeded to 
stain it by my method. I had no difficulty in demonstrating flagella, and 
repeatedly did so without any failures. So I felt justified in concluding that my 
previous cultures had no flagella, and that was the reason of my repeated failures. 
These cultures were from old laboratory strains some years old, and were those used 
for serum diagnosis of typhoid fever, and I was informed that they reacted normally 
