92 
Surra 
a resistance to this drug. Pony no. 91 received six doses only, which 
were not sufficient. Ponies nos. 92 and 93 were treated with atoxyl and 
ars. ac., administered at the same time. This system did not meet with 
any success. 
In the following cases treatment has apparently effected a cure. 
Pony no. C 11. 250 lbs., 5th day after 
1st day 50 c.c. atoxyl. 
3rd ,, 0 - 5 gm. ars. ac. 
5th ,, 50 c.c. atoxyl. 
7th ,, 0-5 gm. ars. ac. 
9th ,, 50 c.c. atoxyl. 
inoculation. (Intermittent dosage.) 
11th day 0-5 gm. ars. ac. 
13th ,, 50 c.c. atoxyl. 
loth ,, 0 - 5 gm. ars. ac. 
17th ,, 50 c.c. atoxyl. 
19th ,, 0-5 gm. ars. ac. 
No return of trypanosomes. Kept under observation 4 mouths. 
Horse no. C 17. About 900 lbs., spontaneous case. In an advanced stage of the 
disease when treatment was commenced. (Intermittent dosage.) 
1st day 100 c.c. atoxyl. 
3rd ,, 1-5 gms. ars. ac. 
5th ,, 100 c.c. atoxyl. 
7th ,, l - 5 gms. ars. ac. 
9th ,, 100 c.c. atoxyl. 
11th day 1-5 gms. ars. ac. 
13th ,, 100 c.c. atoxyl. 
15th ,, 2 gms. ars. ac. 
17th ,, 100 c.c. atoxyl. 
19th ,, 2 gms. ars. ac. 
Trypanosomes reappeared 11 days after the last dose. A second treatment with 
increased doses was given. (Intermittent dosage.) 
1st day 125 c.c. atoxyl. 
3rd ,, 3 gms. ars. ac. 
5th ,, 150 c.c. atoxyl. 
7th ,, 3 gms. ars. ac. 
9th ,, 150 c.c. atoxyl. 
11th day 3 gms. ars. ac. 
13th ,, 150 c.c. atoxyl. 
15th ,, 3 gms. ars. ac. 
17th ,, 150 c.c. atoxyl. 
19th ,, 3 gms. ars. ac. 
No return of trypanosomes. Under observation 12 months. 
Pony no. C 15. 190 lbs., 1st paroxysm. 
1st day 30 c.c. atoxyl. 
3rd ,, 1 gm. ars. ac. 
5th ,, 30 c.c. atoxyl. 
7th ,, 1 gm. ars. ac. 
9th ,, 30 c.c. atoxyl. 
No return of trypanosomes. 
3rd day of disease. (Intermittent dosage.) 
11th day l - 5 gms. ars. ac. 
13th ,, 30 c.c. atoxyl. 
15th ,, 1-5 gms. ars. ac. 
17th ,, 30 c.c. atoxyl. 
19th ,, l - 5 gms. ars. ac. 
Kept under observation 12 months. 
Horse no. C 16. 280 lbs., 1st paroxysm. 
1st ,, 50 c.c. atoxyl. 
2nd ,, 60 ,, 
4th ,, 1-5 gms. ars. ac. 
6th ,, 50 c.c. atoxyl. 
8th ,, 1’5 gms. ars. ac. 
1st day of disease. (Intermittent dosage.) 
10th day 50 c.c. atoxyl. 
12th ,, 2 gms. ars. ac. 
14th ,, 50 c.c. atoxyl. 
16th ,, 2 gms. ars. ac. 
18th ,, 50 c.c. atoxyl. 
No return of trypanosomes. Kept under observation 12 months. 
