4 
their efforts to improve the local sanitary conditions. I can testify to the 
great improvements that have been made in the sanitation of Manaos 
since my arrival in 1905. Commercial enterprises arc rapidly 
advancing, and as commerce extends the population of the Amazon 
region will steadily increase. Modern sanitary methods and anti¬ 
mosquito measures will therefore become a necessity even in the 
smaller towns along the Amazon and its tributary rivers. 
In conclusion, my thanks are due to Sir Rubert Boyce for the 
use of his department in the Thompson- Yates Laboratories, and to 
Mr. Newstead for his advice and help. It 1 ms been . Her of much 
regret to me that serious ocular troubles should have prevented the 
completion of the detailed study of the material designed for this 
report. It is hoped, however, to publish the results of the experi¬ 
mental work at an early date. 
H. W. T. 
