360 Mr. Plimmer and Capt. Fry. Further Results of [June 28, 



Another series of 12 Surra rats was treated with a two hours' decoction of 

 quassia-wood made with the minimum amount of water. Of this three doses 

 were given— 5 minims on the third day and 10 minims on the fourth and 

 ififth days. The trypanosomes in these rats were also entirely unaffected, and 

 the animals died on the sixth — seventh day. It was also tried intravenously 

 in rabbits in doses of 30 minims of the decoction : no effect was produced, and 

 the rabbits died on or about the 42nd day. 



Experiments made in vitro correspond with these results, and will be 

 described later. 



Experiments with Arsenophenylglycin. 



Professor Ehrlich kindly sent some of this substance to Dr. Bagshawe, the 

 Director of the Sleeping Sickness Bureau, with which we have made some 

 initial experiments upon rats. Ehrlich found that Nagana mice could be 

 •cured, in practically every case, with this substance. But the effects on 

 larger animals, so far as we have gone, are not quite so satisfactory, and it 

 compares in this undesirable manner very well with the antimony tartrates, 

 with which we can cure practically every case of Surra in rats, but which do 

 not have anything like the corresponding effects on rabbits, guinea-pigs, and 

 dogs. It is not only in the question of practical dosage that difficulties arise : 

 each kind of animal has a personal equation, and their reaction to a given 

 drug is not similar. This, and the relatively larger dosage in bigger animals, 

 present considerable practical difficulties in the treatment of trypanosomiasis. 



Our experiments have given the following results. Out of eight Surra 

 rats of 180 to 200 grammes weight which were given one dose of 

 25 minims of a 1 in 80 solution of arsenophenylglycin, four died on the 

 19th day with living trypanosomes in their blood, the recurrences having 

 taken place on the 16th— 17th day. Two were given three and five doses 

 respectively of 5 minims of a 1 per cent, solution of lithium antimonyl 

 tartrate on the 17th and following days, and they lived 59 and 51 days. Of 

 the two which are still living (95 days), one has had five doses of 5 minims 

 of a 1 per cent, solution of lithium antimonyl tartrate, beginning on the 

 17th day, and the other had one similar dose given on the day before the 

 recurrences occurred in the other rats. 



The following experiment shows the effect of this substance upon the 

 trypanosomes in the blood, and how much longer it takes than the antimony 

 salts to produce its effects. 



A Surra rat on the fourth day of the disease was treated with 1 c.c. of a 

 2 per cent, solution of arsenophenylglycin (practically the same dose as given 

 to the other rats). 



