Trypanosoma Diseases of Domestic Animals in Nyasaland. 93 



true, at a temperature similar to that which they would find in summer in 

 the low country, while the first three experiments were done in winter and 

 at the ordinary temperature of the laboratory. This no doubt would explain 

 the difference to some extent. Again, goats and sheep infected with 

 T. caprce are unsatisfactory animals to feed flies on. One day the try- 

 panosomes are present in small numbers in the blood, the next day it may 

 be impossible to find any ; very seldom are they in any numbers. It is 

 quite possible, then, that flies may feed on an infected goat or sheep without 

 taking in a single trypanosome. 



Details of the Six Experiments. Five Positive, One Negative. 



The following table gives the principal details in carrying out the six 

 experiments. Laboratory- bred flies were used in all. 



Table II. 



Expt. 



Day of expt. 



Procedure. 



Eemarks. 



444 



1-4 



5-6 

 7-24 



12 flies fed on infected 



Goat 339. 

 Starved. 



Fed on clean Goat 419. 



Trypanosomes appeared in blood of 

 Goat 419 after 23 days. All flies 

 dissected ; 1 infected fly found. 

 Goat 339 contained few trypano- 

 somes in its blood. 



617 



1-4 

 5 



6-63 



33 flies fed on infected 



Sheep 347. 

 Starved. 



Fed on clean Goat 628. 



Trypanosomes never appeared in 

 blood of Goat 628. All flies dis- 

 sected ; all negative. Sheep 347 

 was unsatisfactory ; one day its 

 blood contained a few trypano- 

 somes, the next day none. 



1215 



1-3 



4 

 5-29 



22 flies fed on infected 



Goat 979. 

 Starved. 



Fed on clean Goat 1219. 



Trypanosomes appeared in blood of 

 Goat 1219 after 28 days. All flies 

 dissected ; 1 infected fly found. 



1777 



1-5 

 6 



7-27 



35 flies fed on infected 



Goat 1746. 

 Starved. 



Fed on clean Goat 1803. 



Trypanosomes appeared in blood of 

 Goat 1803 after 26 days. All flies 

 dissected ; 11 infected flies found. 



1784 



1-4 

 5 



6-27 



35 flies fed on infected 



Goat 1746. 

 Starved. 



Fed on clean Goat 1812. 



Trypanosomes appeared in blood of 

 ■ Goat 1812 after 26 days. All flies 

 dissected ; 20 found infected. 



2046 



1-5 

 6 



7-18 



19-20 

 21-23 

 24-25 

 26-36 



33 flies fed on infected 



Goat 1912. 

 Starved. 



Fed on clean Monkey 



2066. 

 Starved. 



Fed on clean Goat 2102. 

 Starved. 



Fed on clean Monkey 

 2066. 



Trypanosomes appeared in blood of 

 Goat 2102 after 27 days. All flies 

 dissected ; 13 found infected. 



I 2 



