THE SPIROCHMTACE& 635 



must in some instances present strict, in others only partial 

 anaerobic conditions. 



The preparation of such culture media is done under strict 

 aseptic conditions as the heating of the media for purposes 

 of final sterilization robs them of their usefulness. 



Noguchi, whose investigations in this field have con- 

 tributed so much to our knowledge on the subject, finds 

 that in general a medium made up of about 12 to 15 c.c. 

 of sterile ascitic or hydrocele fluid to which is added a few 

 drops of citrated blood and a bit (about the size of a bean) 

 of fresh rabbit kidney, serves very well for the cultivation 

 of most blood spirochetes. He has also had success with 

 the following mixture: 



Rabbit serum ; . 1.5 parts 



Ringer's solution 1 . . 4.5 " 



Citrate plasma 1.0 " 



If it be desirable to stiffen the medium, and certain 

 spirochetes develop better in such than in fluid media, sterile 

 agar (free of peptone and sugar) in the proportion of 2 per 

 cent, may be added. 



For those species requiring partial anaerobic conditions 

 a little sterilized paraffin oil may be run over the surface. 

 For those requiring strict anaerobic conditions tubes should 

 be kept in an oxygen-free atmosphere (see anaerobic 

 methods) . 



The citrated blood in the above mixture may be drawn 

 under aseptic conditions from the animal or person whose 



1 Ringer's solution: 



Sodium chloride 10.0 grams 



Potassium chloride 0.2 " 



Calcium chloride 0.2 " 



Sodium bicarbonate 0.1 . " 



Glucose 1.0 " 



Water . 1000.0 c.c. 



