382 IMPORTANT VARIETIES OF FISSION-FUNGI. 



It is typically found in the blood and spleen of recur- 

 rent fever cases, hardly ever during the afebrile periods 

 (an exception proved by Naunyn) ; demonstrated by Kar- 

 linski to be the cause of a part of the cases of febrile 

 icterus (C. B. xi, 26). 



It stains readily with the usual anilin dyes. Giinther 

 recommends that the dried and fixed preparation be pre- 

 viously freed of part of the albuminous bodies by means 

 of a 1% to 5% acetic acid solution. It is not stained by 

 Gram's method. 



No cultures have so far been successful. According to 

 Pasternatzky, the spirochsete may be preserved alive for 

 about ten days if a leech is allowed to fill itself from a 

 case of recurrent fever, and then is kept upon ice. 



Inoculation experiments have succeeded only upon man 

 and monkeys. The .monkeys become sick after about 

 three and a half days, but present only the initial attack 

 of fever and no recurrence. Extirpation of the spleen 

 makes the disease more dangerous for the monkey. 



