PATHOGENIC SPIRILLA. 601 
ministration of the opium a bouillon culture of the cholera spirillum 
is injected into the stomach through a pharyngeal catheter. Asa 
result of this procedure.the animal shows an indisposition to eat and 
other signs of sickness, its posterior extremities become weak and 
apparently paralyzed, and, as a rule, death occurs within forty-eight 
hours. At the autopsy the small intestine is found to be congested 
and is filled with a watery fluid containing the spirillum in great 
numbers. Comparatively large quantities of a pure culture injected 
into the abdominal cavity of rabbits or of mice often produce a fatal 
result within two or three hours; and Nicati and Rietsch have ob- 
tained experimental evidence of the pathogenic power of filtered cul- 
tures not less than eight days old. The most satisfactory evidence 
that this spirillum is able to produce cholera in man is afforded by an 
accidental infection which occurred in Berlin (1884), in the case of a 
young man who was one of the attendants at the Imperial Board of 
Health when cholera cultures were being made for the instruction of 
students. Through some neglect the spirillum appears to have been 
introduced into his intestine, for he suffered a typical attack of 
cholera, attended by thirst, frequent watery discharges, cramps in 
the extremities, and partial suppression of urine. Fortunately he 
recovered ; but the genuine nature of the attack was shown by the 
symptoms and by the abundant presence of the ‘‘ comma bacillus” 
in the colorless, watery discharges from his bowels. Nicati and 
Rietsch observed a certain degree of attenuation in the pathogenic 
power of the spirillum after it had been cultivated for a considerable 
time at 20° to 25° C. ; and the observation has since been made that 
cultures which have been kept up from Koch’s original stock have 
no longer the primitive pathogenic potency. 
Cunningham, as a result of researches made in Calcutta (1891), 
arrives at the conclusion that Koch’s “comma bacillus” cannot 
be accepted as the specific etiological agent in this disease. This 
conclusion is based upon the results of his own bacteriological 
studies, which may be summed up as follows: First, in many un- 
doubted cases of cholera he has failed to find comma bacilli. Sec- 
ond, in one case he found three different species. Third, in one case 
the reaction with acids could not be obtained. From sixteen cases 
in which Cunningham made cultures he obtained ten different vari- 
eties of comma bacilli, the characters of which he gives in his pub- 
lished report. It may be that in India, which appears to be the 
permanent habitat of the cholera spirillum, many varieties of this 
microorganism exist ; but extended researches made in the laborato- 
ries of Europe show that Cunningham is mistaken in supposing that 
spirilla resembling Koch’s “ comma, bacillus” are commonly present 
in the intestine of healthy persons. The view advocated is that 
