58 THE BACTERIA IN ASIATIC CHOLERA. [CH. 



rounded forms are discoid or spheroidal. I am inclined to 

 think that some of them, at any rate, are discoid, because 

 in the fresh state, and suspended in fluid, I have noticed 

 under the microscope that when they float and roll they 



O 



FIG. 17. FROM AN ARTIFICIAL CULTIVATION OF CHOLERAIC COMMA-BACILLI ON 



NEUTRAL AGAR-AGAR JELLY AT ORDINARY TEMPERATURE, AFTER A FEW WEEKS. 



Some of the comma-bacilli have become converted into circles, which by division 



give origin to two semicircular comma-bacilli. 



Magnifying power about 700. 



present alternately a broad and narrow surface ; but there is 

 evidence that some are distinctly spheroidal, since when 

 rolling they always show a circular outline. The next and 

 important question is : What is the meaning of this change ? 



*>*** * * f 



FIG. 18. FROM A SIMILAR FIG. 19. FROM A SIMILAR 



PREPARATION. PREPARATION. 



Koch, in a somewhat impatient way, says that these forms 

 described by me (which, as will be shown presently, are the 

 first stages of a longitudinal division) are a supposed dis- 

 covery " resting on an erroneous interpretation of the in- 

 volutional (i.e. degenerative) forms of the cholera-bacilli." 



