264 The Control of Mosquitoes 



Each of these dishes was a mosquito incubator 

 of a most efficient type. 



The result of all these factors favoring mos- 

 quito propagation was, that the two cities har- 

 bored vast niimbers of these insects. The 

 Aedes calopus was the commonest mosquito in 

 Panama, and the mosquito bars used by some 

 of the natives were intended particidarly as a pro- 

 tection against their annoyance. 



Turning to the records" of the four years im- 

 mediately preceding the inauguration of sanitary 

 work on the Isthmus, the available records of 

 deaths from yellow fever in the city of Panama 

 show: 



109 deaths in 1900 



5 " " 1901 

 202 " " 1902 



51 " ." 1903 



These figures, however, indicate the yellow 

 fever mortality in a population including few non- 

 immunes. The accuracy of these statistics may 

 also be challenged, as there was practically no 

 sanitary organization in this province of Col- 

 ombia, nor was the reporting of yellow fever 

 compulsory. 



With myriads of Aedes calopus on the wing, with 



