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); demonstt:ated 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- 

 viouslj' 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 

 Pasternatzk}', the spirochsete may be preserved alive for 

 aljout 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. 



