PATHOGENIC SPIRILLA. 601 



ministration of the opium a bouillon culture of the cholera spirillum 

 is injected into the stomach through a pharyngeal catheter. As a 

 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. Mcati and 

 Riet3eli 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 



