90 THE BACTERIA IN ASIATIC CHOLERA. [CH. 



very much the same as those of the choleraic comma-bacilli 

 they grow rapidly and well at temperatures of from 30 

 37 C. ; (/) on boiled potato Finkler's comma-bacilli grow 

 well even at temperatures of i8-22 C., and from the 

 spot of inoculation a smeary greyish-brown film soon ex- 

 pands, and gradually thickens ; in a few days at 20 C, the 

 growth is copious ; in this respect then a marked difference 

 exists between the two comma-bacilli ; (g) in nutritive 

 gelatine in plate-cultivation the character and aspect of the 

 colonies of Finkler's comma-bacilli is very similar to those 

 of the choleraic comma bacilli, except that the colonies 

 make their appearance much sooner, and having appeared, 

 grow much more rapidly than those of the choleraic com ma- 

 bacilli; (h) they liquefy the gelatine, but the liquefied 

 gelatine both in plate-cultivation and in tubes is less clear 

 than is the case with the choleraic comma-bacilli ; on com- 

 paring a gelatine tube of Finkler's comma-bacillus with one 

 of the choleraic comma-bacilli, after a week or more the 

 liquefied gelatine in the latter is more clear than in the 

 former, although in both it is not quite clear ; gelatine tubes 

 in which Finkler's comma-bacillus has been growing, and 

 in which the gelatine with the exception of the deepest parts 

 has become completely liquefied, show the same whitish 

 or greyish-brown precipitate as similarly advanced culture- 

 tubes of choleraic comma-bacilli, the liquefied gelatine being 

 only slightly opaque and in the upper layers almost trans- 

 lucent, while in similarly advanced culture-tubes of choleraic 

 bacilli the liquefied gelatine is a little less opaque, and in 

 many tubes there is present on the surface a granular 

 whitish filmy pellicle (p. 78) ; (z) the best test of distinction 

 is no doubt that pointed out by Koch, namely, the mode 

 of growth and the rapidity with which the two kinds of 

 comma-bacilli grow in nutritive gelatine of 10 per cent. 



