SPIRILLUM CHOLERA ASIATICS. 569 



choleraic origin; Finkler and Prior, for instance, found 

 them in the diarrhceic stools of cholera nostras, Deneke 

 in cheese, Lewis and Miller in saliva. All of these 

 organisms, however, differed in many respects from 

 Koch's comma bacillus, and since then it has been 

 proved that none of them was affected by the specific 

 serum of animals immunized to cholera; and gradually 

 the exclusive association of Koch's vibrio with cholera 



FIG. 74. FIG. 75. 



Contact smear of colony of Contact spirilla preparation from plate 



cholera spirilla from agar. culture of cholera. X 800 diameters. 



X 700 diameters. (DUNHAM.) (DUNHAM.) 



became almost generally acknowledged. It is now re- 

 garded by bacteriologists everywhere to be the specific 

 cause of Asiatic cholera. 



Morphology. Curved rods with rounded ends which 

 do not lie in the same plane, from 0.8// to 2/* in length 

 and about 0. 4// in breadth. The curvature of the rods 

 may be very slight, like that of a comma, or distinctly 

 marked, particularly in fresh unstained preparations 

 of full-grown individuals, presenting the appearance 

 of a half -circle. By the junction of two vibrios 

 S-shaped forms are produced, and under unfavorable 



