94 PRACTICAL ZOOLOGY 



great energy and the measures were based almost entirely upon 

 a warfare against the yellow fever mosquito. The disease be- 

 gan almost immediately to abate, and the result at the close of 

 the season indicated 460 deaths, as against 4046 in 1878, a 

 virtual saving of over 3500 lives. 1 



Control in Panama Canal Zone. — One of the most 

 interesting examples of the eradication of disease by the 

 destruction of mosquitoes is the campaign of the United 

 States Government in the Panama Canal Zone which was 

 begun in 1904.' 



In Panama, as in Havana, the population had depended prin- 

 cipally upon rain water for domestic purposes, so that every 

 house had cisterns, water barrels, and such receptacles for catch- 

 ing and storing rain water. The city was divided into small dis- 

 tricts with an inspector in charge of each district. This inspector 

 was required to cover his territory at least twice a week and to 

 make a report upon each building with regard to its condition 

 as to breeding places of mosquitoes. All the cisterns, water 

 barrels, and other water receptacles in Panama were covered as 

 in Havana, and in the water barrels spigots were inserted so that 

 the covers would not have to be taken off. Upon first inspection, 

 in March, 4000 breeding places were reported. At the end of 

 October less than 400 containing larvae were recorded. This 

 gives one a fair idea of the consequent rapid decrease in the 

 number of mosquitoes in the city. These operations were 

 directed primarily against the yellow fever mosquito, and 

 incidentally against the other common species that inhabit rain- 

 water barrels. Against the Anopheles in the suburbs the same 

 kind of work was done as was done in Havana, with exception- 

 ally good results. 



The same operations were carried on in the villages between 

 Panama and Colon. There are some twenty of these villages, 

 running from 500 to 3000 inhabitants each. Not a single in- 



1 Howard, L. O., Bulletin 78, Bureau of Entomology, U. S. Department of Agri- 

 culture. 



