144 THE HOUSE FLY— DISEASE CARRIER 



pital Service. The fly gatherings were begun about 

 June 19th and continued to October 19th, having cov- 

 ered a period of four of the hottest months in the sea- 

 son and those in which flies are most troublesome. The 

 method used was to supply such of the members of the 

 Bureau force as lived in distinct and separate sections 

 of the city with a quantity of sticky fly paper with in- 

 structions to expose a sheet every other day for a 

 period of forty-eight hours. The sheets w^ere then re- 

 turned to the Bureau and the flies carefully counted 

 and recorded upon specially prepared cards bearing ad- 

 dress and date of each exposure, together with such 

 data as could be secured concerning the conditions of 

 nearby stables and manure heaps. Certain parts of the 

 city, among the slums and along the water front, were 

 not reached by the regular employes of the Bureau, 

 but, that these sections might be represented in the re- 

 port, two assistants were detailed for the purpose and 

 made regular rounds on bicycles, collecting fly-laden 

 sheets and leaving fresh paper three times a week. Sun- 

 day, of course, was a day of rest, and this fact inter- 

 fered to some extent with the counts, since in case of 

 papers exposed in meat shops and restaurants flies were 

 usually so plentiful that the maximum catching ca- 

 pacity of the paper was reached within forty-eight 

 hours. 



Sixty-two stations were located throughout the city. 

 At the end of the season the results were tabulated and 

 the curve of increase was plotted. At the same time 

 the Public Health and Marine-Hospital Service had 



