SPIRILLA RESEMBLING CHOLERA. 453 



ilium. At times the growth may be a little more rapid. 

 The growth on agar is very luxuriant, and gives off a 

 pronounced odor of indol. Loffler's blood-serum is ap- 

 parently not a perfectly adapted medium, but upon it the 

 organisms grow, with resulting liquefaction. Upon po- 

 tato at the point of inoculation there is a thin, glazed, 

 more or less dirty yellow, shading to brownish deposit that 

 is sometimes surrounded by a flat, dry, lusterless zone. 



In litmus milk a slightly reddish tinge is found after 

 twenty-four hours at body temperature. After forty-eight 

 hours this is increased and the milk is coagulated. In 

 peptone solutions indol is produced. No gas is pro- 

 duced in glucose-containing culture-media. The organ- 

 ism is a facultative anaerobic spirillum. The thermal 

 death-point is 50 C. for five minutes. 



The organism is pathogenic for pigeons, guinea-pigs, 

 and mice. The pathogenesis is much like that of the 

 Spirillum Metschnikovi. No Pfeiffer's phenomenon was 

 observed with the use of the serum of immunized ani- 

 mals. 



Immunity was produced in pigeons, and it was found 

 that their serum was protective against both the Vibrio 

 Schuylkiliensis and Spirillum Metschnikovi, the immun- 

 ity thus produced being of about ten days' duration. 



In a second paper by Abbott and Bergy x it was shown 

 that the vibrios were found in river water during all 

 four seasons of the year, and in all parts of the river 

 within the city, both at low and at high tide. They were 

 also found in the sewage emptying into the river. The 

 spirilla were also found in the water of the Delaware 

 River as frequently as in that from the Schuylkill. 



One hundred and ten pure cultures of spirilla were iso- 

 lated from the sources mentioned and subjected to routine 

 tests. It was found that few or none of them were iden- 

 tical in all points. There seems, therefore, to be a family 

 of river spirilla related to each other like the different 

 colon bacilli are related. 



1 Journal of Experimental Medicine, vol. ii., No. 5, p. 535. 



