a! a 
1910.] Szckness studied by Precise Enumerative Methods. 199 
Cessation of Multiplication, probably depending on the following con- 
ditions :— 
(a) The presence of anti-bodies in the serum. 
(0) The large increase of leucocytes, especially mononuclears. 
(iii) The Trypanosomes remaining between the Rises are Resistant Forms, and 
tend to become spherical, especially in the internal organs. Vide paper by 
H. B. Fantham. 
These resistant spherical forms also occur after atoxyl treatment (Moore 
and Breinl). 
N.B.—The reference to the virulence of this trypanosome and to the cycle 
in rats and guinea-pigs is taken from the paper on enumerative studies in 
rats, guinea-pigs, and rabbits by J. G. Thomson and H. B. Fantham. 
The virulence of this strain was also noticed by L. E. W. Bevan and 
Malcolm Macgregor (‘Journal of Comparative Pathology and Therapeutics,’ 
June, 1910), who inoculated animals from our patient before he left 
N.E. Rhodesia. 
