that an Atoxyl-resistant Surra strain reacted to Antimony in the 
same-way as a normal strain. A preventative action was only noticed 
if the drug and the parasites were injected simultaneously in twc 
diiferent distant places. 
In our hands,^ Sodium antiinonyl tartrate did not give such 
promising results in the treatment of rats, a fact which might be due 
to the use of an especially virulent strain of T. equiperdum. One 
horse injected with a §train of cattle trypanosomes brought back from 
the Congo, and one donkey infected with an Atoxyl-resistant strain 
of Ngana, were treated with Sodium antimonyl tartrate in fairly large 
doses. In both cases the drug caused the prompt disappearance of 
the parasites ; the interval between the relapses, how’ever, became 
shorter and shorter after each injection, and finally both animals 
succumbed to the disease. 
Manson^ was the first to administer Sodium antimonyl tartrate to 
a case of Sleeping Sickness. As Atoxyl given in large doses did not 
seem to have any effect on the trypanosomes, a treatment of Antimony 
in small doses was begun. It caused the disappearance of the 
parasites, but eighteen days afterwards parasites w’ere again seen in 
the peripheral circulation. As the injection had caused intense 
irritation and pain, two grains of Antimony were given by the mouth: 
this was followed by nausea, and seemed to increase the mental 
depression of the patient. Antimony treatment was discontinued, 
and Atoxyl again given. 
iiiiCliLs 
with different laboratory strains of pathogenic trypanosomes. 
According to their results they were able to separate the strains into 
two groups. The parasites of the first group disappeared after a 
single injection ; Surra and Dourine belonging to this group. In the 
second group, to which all other strains belong, the parasites 
disappeared after the injection of Tartar emetic, but only to reappear 
within a few days. The negative phases after each injection became 
rter and shorter, and the animals finally succumbed to the disease. 
In the discussion, Laveran? * states that in his hands, Tartar 
prove very satisfactory in guinea-pigs, as after the 
p isappearance of the parasites following the first injection, 
pses occurred very frequently. Sulphide of Antimony, in his 
P e, is much less active than Sulphide of Arsenic (orpiment). 
