G. H. F. Nuttall 
149 
out. Finally I should like to state that my laboratory assistant, 
Mr B. G. Clark, has been of material assistance to me in carrying out 
the foregoing investigation. 
Note on Experiments with Spirochaeta ohermeieri. 
Since the foregoing pages went to press T have, through the courtesy 
of Geheimrath C. Fraenkel of Halle, succeeded in obtaining a strain of 
the true Sp. ohermeieri, which had been brought from Russia. Although 
my experiments with this spirochaete have not been concluded, the 
results I have obtained appear worth recording, more particularly 
because a positive infection experiment with Acanthia lectularia was 
obtained. 
Observations on the behaviour of Spirochaeta ohermeieri 
in the body of Acanthia lectularia. 
Experiment I, at 12° C. 
Time when bug 
was examined 
after feeding 
Appearance of spirochaetes in gut contents 
Bugs fed on 
Fresh 
Stained 
27. iv. 1908 
6 hrs 
Very active 
Many rigid spirals, r.b.c. all staining 
well. 
22 „ 
Fairly active 
Ditto, also a few worm-like. 
27 „ 
Sluggish 
Ditto. 
47 „ 
Almost motionless 
Ditto. 
71 „ 
? Motionless 
Ditto. 
96 „ 
Motionless 
Ditto, but r.b.c. begin to vanish. 
120 „ 
None found 
None found, r. b. c. gone. 
Note: One spirochaete found in coelomic fluid taken from leg after 6 lira., the 
examination 
in all other cases proved negative. 
Experiment II., at 
25° C. 
27. iv. 1908 
3 hrs 
Some very active 
Many rigid spirals, a few worm-like, 
others slow 
r. b. c. all staining well. 
20, 27, 45 hrs 
All motionless 
Ditto, but r. b. c. fading. 
72 hrs 
No spir. found 
No spir., no r. b.c. found. 
Note: No spirochaetes found in coelomic fluid from leg at any time. 
Summary of foregoing experiment. 
It will be seen from the foregoing protocols that the spirochaetes 
still showed movement after 
27—47 hours at 12° C. but were motionless after 96 hours. 
3 „ 25° C. „ „ 20 ,, 
Parasitology i 
10 
