REPORT OF TKAVERRINO PATHOLOGIST AND PROTOZOOLOOIST 
139 
maintained it had spread from Abyssinia. At Bor I examined the blood of a large number of 
cattle which had just arrived from El Obeid. They were all healthy, and no trypanosomes 
were found. The Piroplasmata affecting the Sobat cattle are figured on Plate IV., figs. 4 and'5. 
Treatment of Trypanosomiasis 
A certain number of experiments were made with animals suffering from trypanosomiasis 
and one of the colours of benzidine (naphthalene-diamine-disulphonic acid 273G 4- benzidine) 
which elsewhere 1 had found useful in treating mice artificially infected with Trypanosoma 
dimorphon. In the present instance the animals employed were mules and donkeys which had 
become infected naturally, presumably by the bite of Glossina morsitans, with the trypanosome 
which is probably T. pecaudi. The results obtained were disappointing.’ In no case did the 
drug bring about the complete disappearance of the trypanosomes from the blood, though they 
were always reduced in number. Large quantities of drug had to be given in solution hypo¬ 
dermically or intra-muscularly. One gramme dissolved in the minimum quantity of distilled 
water was given at each injection. This quantity caused a very considerable amount of oedema 
around the point of injection, and in some instances abscess developed. Post mortem the 
animals were well coloured, in spite of which the trypanosomes had not disappeared nor was it 
clear that the life of the animals had been prolonged. Similar results were obtained in the 
case of rats artificially infected with this trypanosome. The resistance of this trypanosome to 
the benzidine colour in question is in favour of the view' that it is distinct from T. dimorphon. 
Treatment of Trypanosomiasis by ‘Soamin’ 
I have been able to try the action of an arsenic preparation recently put on the 
market under the name of Soamin. The composition is sodium para-aminophenylarson- 
ate, with the formula Ci;H4.NH2.As0(0H)(0Na),5H.20. These experiments were conducted 
with ordinary wild rats, which w'ere inoculated with the Sudan trypanosome (T. peca^^d^) 
obtained from donkeys and mules. This strain of trypanosomes would infect rats about 
five days after inoculation. On the sixth day the trypanosomes were generally present in large 
numbers, and it was on this day that a dose of the drug w'as administered. If untreated 
the rats invariably died in about one month after inoculation. In employing the drug it 
W'as soon found that unless perfectly fresh solutions were used toxic symptoms were produced. 
The solution generally employed was that of 1 grain (0'064 gramme) of the drug in 5 c.c. of 
distilled w'aler. The drug is readily soluble in cold distilled water, but warming facilitates 
solution and does not appear to produce any alteration. A rat could endure tw'o-tifths of 
a grain of the drug in freshly prepared solution (2 c.c.). A. solution a few' days old became of a 
yellow or light brown tint, and of this 2 c.c. would produce toxic symptoms in rats, and 
frequently kill them. On one occasion i c.c. of such a solution killed an infected rat. 
The drug was used on ten infected rats. The “control” untreated rats invariably died 
from the results of their infection. It will be seen from the details of the experiments given 
below that three of these rats died from the toxic effects of the drug in old solutions (Nos. 2, 3, 4). 
Of the remaining seven rats two died, one having been treated three times and the other 
tw'ice, while five were permanently cured. One of the five suffered from relapse after the 
first administration of the drug, but w'as cured after further treatment. 
' Professor Mesnil informs me that Dr. Bmiffard has experimented with this colour in the treatment of 
animals infected with T. pecaudi in tlie French Sudan. His results are similar to those recorded here. 
(“hromo- 
therapy 
Treatment 
with ‘ JSoamin, ’ 
an arsonate 
Recoveries 
amongst rats 
