1907.| Experimental Treatment of Trypanosomasis in Rats.  '7 
be found, and in the other only one in an ordinary blood preparation (see 
Plate 1). In these cases a few trypanosomes can sometimes be found in 
the liver, and these are extremely active and in no way inconvenienced by 
the drug; whether these are the forms which can persist, and need to be 
tired out by successive doses, we cannot say at present, but their extreme 
activity, when all the others have disappeared, is suggestive. We have 
up to the present not detected any morphological differences in them. 
A striking instance of the power of this compound over trypanosomes is 
seen in the case of a guinea-pig which was inoculated with Z’rypanosoma 
Gambiense on April 9. From July 3 to September 16, trypanosomes were 
present in the blood, latterly in quantity, and the animal was dying on 
September 16; its eyelids were cedematous and nearly closed; it had cedema 
of the genitals and anus, and a discharge of bloody mucus from the rectum, 
and its hair was coming out in large patches. At this date—September 16— 
it was given 0°5 c.c. of a 1 per cent. solution; on the 17th the trypanosomes 
had entirely disappeared, and 0°75 c.c. was given; on the 19th the animal 
to all appearances was quite well, and on this day, and on 21st and 26th, 
1 ec. was given. The cedema disappeared and it continued to look well, 
and showed no more trypanosomes. It lived until October 14, when it 
died ; post mortem the organs were congested and the kidneys were inflamed 
and the urine in the bladder contained albumen. The fact that the guinea- 
pig was moribund when the treatment was commenced may reasonably 
account for the pathological condition. 
The following table shows the general results, as obtained so far, of the 
treatment with sodium antimony] tartrate. Of the 39 rats enumerated in 
this table, the first 3 had been treated at first with antimony glycine ; and of 
the 11 of the remaining 36 which have died, 6 did not die of the disease, and 
there remain alive and well 3 of 52 days, 1 of 49,7 of 44, 8 of 43, 4 of 31, 
and 2 of 21; and of these 25, 23 have had no recurrence. It will be seen 
that 8 of the rats (4 Nagana and 4 Surra) have been treated with mercury in 
addition to the sodium antimonyl tartrate, in order to see if these obtained 
thereby any advantage over those not so treated. So far as we can tell at 
present, there seems to be no obvious advantage: one of the Nagana rats 
treated with liq. hydrarg. perchlor. has had three recurrences, and one Surra 
rat treated with succinimide of mercury has died after one recurrence. 
Sodium Arsenyl Tartrate. 
As the results with the sodium antimonyl tartrate were so definite, it 
seemed worth while to investigate the effect of the corresponding arsenic 
compound. 
