412 JOURNAL, BOMBAY NATURAL HISTORY SOCIETY, Vol. XX. 



to these also. Wherever numerous wells, cisterns and tanks 

 infected by this mosquito are found to exist, old tin-pots, collec- 

 tions of water on pieces of old machinery, disused mortar mills, 

 stone troughs and everything that can hold a little fresh water for 

 a few days, is very likely to be found to contain larvae during the 

 rainy season. Thus I have found them in pigeon troughs in the 

 street, in tins and old cans in back-yards, in old paint pots, and 

 in little collections of water in the hollows and crevices of both old 

 and new machinery. 



On several occasions I have found that paint pots and tins left 

 on the roofs of houses in which painters had been working, had 

 become most prolific breeding places. In one case twenty such 

 tins were present on a roof, all breeding these mosquitoes, and the 

 tenants of the top floor complained of having suffered considerably 

 from fever, which they put down to " bad smells " and the exist- 

 ence of dirty puddles in the street. In another case I found that 

 some one was keeping fowls on a terrace roof and tins and tubs of 

 water were placed there for their use. The tubs and tins supplied 

 the fowls with water and the household with malaria-carrying mos- 

 quitoes. Several times I have come across charming little terrace 

 gardens nicely arranged on the roof of a house, and nearly always 

 providing a selection of breeding places for N. stepJwnsi in the shape 

 of tins, tubs, and pots wherein water was allowed to remain. Two 

 or three times large tin baths have been found upon terrace roof, 

 forming excellent breeding places for N. stephensi, larvas of which 

 were present in large numbers. These observations show that 

 terrace roofs may form a considerable source of danger in assisting 

 the spread of malaria, when made use of as a sort of elevated back- 

 yard or lumber store. 



Special Breeding Places. 



Besides the breeding places of which I have spoken Bombay 

 possesses certain special ones of which every one should know. 

 Among the more important of these are the two reservoirs which 

 supply Bombay with water. At Mazagon the Bhandarwada 

 reservoir is provided with a number of open sand filter beds each 

 with its cushion well. Now these filter-beds seem to be just adapt- 



