YELLOW FEVER PROPHYLAXIS IX XEW ORLEANS 9 



the populated centres and less frequently found in the rural districts. Although 

 preferably a cistern breeder it occasionally seeks out other places. The Medical 

 Societies Commission found as the result of an examination of 21 street gutters, 

 the Stegomyia no less than 16 times. If driven by screening and oiling from its 

 usual breeding place in clean water cisterns the eggs appear to be able to 

 develop not only in the contaminated water of the gutters, but even in concen- 

 trated faecal matter (Dupree and others). Reed and Carroll found Stegomyia 

 breeding in 



(i) Rain water barrels, 



(2) Sagging gutters containing rain water, 



(3) Tin cases used for removing excreta, 

 (4} Cesspools, 



(s) Tin cans placed about table legs to prevent the inroads of red ants, 

 (6) In the collections of water at the base of the leaves of the Agave 

 americana. They state that the presence of fascal matter is not 

 objectionable. In the map of the mosquito distribution of New 

 Orleans drawn up by the Commission it will be seen that the present 

 epidemic of Yellow Fever corresponds with the Stegomyia distri- 

 bution. 

 The Prevention of Yellow Fever, Medical Record, New York, Oct., igoi. 



In Belize in British Honduras I found the .Stegomyia breeding in 

 immense numbers in the clean water receptacles, such as vats, iron 

 tanks, barrels, kerosene tins and odd receptacles. I also found 

 them breeding in the irregular pockets present in the logs of 

 logwood which, being exposed to the rains, accumulated water. The 

 stained, almost black, water in these crevices did not appear to 

 prevent the development of the wrigglers. I also found them in a 

 cooling water barrel by the side of the furnace in a blacksmith's shop, 

 and the same observation was made in New Orleans during the 

 epidemic. Altogether I examined in conjunction with Mr. Burchell, 

 the Superintendent of Pubhc Works, and Drs. Harrison and Heusner, 

 of Belize, 836 separate lots in the town of Belize, in which there were 

 present 1,342 barrels, 760 vats and tanks, 91 wells, and innumerable 

 kerosene tins and odd receptacles. I took samples of the larvae, unless 

 the adult Stegomyia was found, and developed '\hem in the labora- 

 tory, and, as the result, concluded that the Stegomyia was present 

 in certainly 50 per cent, of the lots in the town. I never found 

 Anopheles in these receptacles, and Culex comparatively infrequently. 

 On the other hand Anopheles larvae were present in the clean water 

 pools and gutters in the streets and waste places, whilst Stegomyia 



was absent. 



T/ie Gutter Mosquito. 



The open gutters, like the system of cisterns, are a feature in New 

 Orleans (fig. i). As previously mentioned, there is little or no 



