144 Spirochaetosis 
Examined with negative results on the 22nd, 24th, 26th, 27th, 29th Nov. and 
2nd Dec. 1910. 
Exp. 29. 25th Nov. 1910. Mouse; intra-peritoneal injection of 0'5 c.c. of 
defihrinated relapsing fever blood in 1‘5 c.c. saline. 
26th Nov. 1910. Spirochaetes detected; mouse killed and blood injected into 
mice of Exps. Nos. 50, 51. 
Exps. 30, 31. 25th Nov. 1910. Two mice ; intra-peritoneal injection of 0-5 c.c. 
defihrinated relapsing fever blood in 1'5 c.c. saline. 
Spirochaetes seen on two following days. Negative the 29th Nov. and 
2nd Dec. 1910. 
Exps. 32-34. 1st Dec. 1910. Three white rats; intra-peritoneal injection of 
0'5 c.c. relapsing fever blood in 1'5 c.c. saline. 
All three showed spirochaetes in their blood the next day and were negative the 
following day. 
Exp. 35. 1st Dec. 1910. Mouse; intra-peritoneal injection of 0‘5 c.c. of 
defihrinated relapsing fever blood in 0'5 c.c. saline. 
Spirochaetes found next, but none the following day. 
Exps. 36-40. 8th Dec. 1910. Five mice; intra-peritoneal injection of 0'3 c.c. 
defihrinated relapsing fever blood in 0‘5 c.c. saline. 
One showed spirochaetes next day only. 
Spirochaetes found in all four animals the next two days, but none on the 
third day. 
IV. Experiments in which infection followed the first atid subsequently 
repeated inoculations. 
Exp. 41. Same mouse as in Exp. No. 27. 14th Dec. 1910. Intra-peritoneal 
injection of 0'15 c.c. defibrinated relapsing fever blood in 0'5 c.c. saline. 
15th Dec. 1910. Spirochaetes detected. 
16th Dec. 1910. Atypical, short spirilla seen, possibly bacteria (?). 
17th Dec. 1910. Negative. 
Exp. 42. Same mouse as in Exp. No. 28. 14th Dec. 1910. Intra-peritoneal 
injection of 0T5 c.c. defibrinated relapsing fever blood in 0-5 c.c. saline. 
15th Dec. 1910. Spirochaetes present. 
16th Dec. 1910. Negative. 
Exp. 43. Same mouse as in Exp. No. 31. 14th Dec. 1910. Intra-peritoneal 
injection of 0-3 c.c. defibrinated relapsing fever blood in OA c.c. saline. 
15th Dec. 1910. Spirochaetes detected with peculiar lashing, trypanosome-like 
movements. Negative next day. 
Exp. 44. Same mouse as in Exp. No. 36. 14th Dec. 1910. Intra-peritoneal 
injection of 0-3 c.c. of defibrinated relapsing fever blood in 0’5 c.c. saline. 
Spirochaetes found the two following days. Mouse was killed and blood used 
for Exps. Nos. 56, 57. 
