in.] CHOLERAIC COMMA-BACILLI. 57 



In a stool from an acute case of cholera I have seen these 

 forms in enormous numbers ; in some fields of the micro- 

 scope the transitional forms between complete circles and 

 typical commas being very numerous. In neutral Agar-agar 

 mixture kept at the temperature of the room (between 18 

 and 20 C.) after three, four, and more weeks, I have 

 seen this change occurring in many of the commas ; in 

 alkaline Agar-agar mixture I have also noticed it, but more 

 rarely. The best specimens I possess were made from 

 cultures in neutral Agar-agar about four to six weeks old. 

 Preparations made of such cultures show in some fields of 

 the microscope the typical comma-bacilli only in a few 



W 



FIG. 16. FROM A RECENT ARTIFICIAL CULTIVATION OF CHOLERAIC 

 COMMA-BACILLI IN ALKALINE AGAR-AGAR JELLY. 



Magnifying power about 700. 



examples, most of them showing in some stage or other the 

 above vacuolation and transformation into circular or oval 

 organisms. Some of these, although already completely 

 rounded, nevertheless do not yet show in their interior a 

 complete cavity, but two or three small cavities separated by 

 remnants of protoplasm. 



As the comma-bacilli from which these rounded or oval 

 forms take their origin are of different lengths, so do also 

 the sizes of these rounded or oval forms differ, the small 

 commas giving origin to small, the large commas to large, 

 rounded or oval forms. The question is, whether these 



