3I0SQUIT0ES IN GENERAL 33 



Another instance of the necessity of searching- out of 

 the way places for mosquitoes and larvis has recently 

 been told me by Dr. James Carroll, U. S. A., a member of 

 the Yellow-fever Commission. Visiting an army officer in 

 charge of a post in Cuba, he found the yellow-fever mos- 

 quito in numbers in the quarters. The officer in charge 

 could not imagine where they came from, as, under orders, 

 he had had every possible breeding-place exterminated, 

 either by surface drainage or by petrolizing. Dr. Carroll 

 noticed that the table in the dining-room had been insu- 

 lated by placing its legs in small jars of water, the surface 

 of the water being carefully covered with kerosene. In 

 going into an adjoining room, however, he found that a 

 table there had also been insulated in the same way, but 

 that the water about only one of the legs of the table had 

 been covered with kerosene, while the jars under the 

 other three legs were swarming with mosquito larvge. 

 This was the fault of the orderly, an Irishman, who liter- 

 ally obeyed orders in kerosening such vessels as had been 

 pointed out to him, but no more. Enough mosquitoes 

 bred in these three jars to stock a large community. 



It is common opinion that mosquitoes do not need 

 standing water in which to breed. It is generally sup- 

 posed by non-observant people that they are able to breed 

 in wet grass, and it is a common observation, as recently 

 expressed by a correspondent of the Pacific Rural Press 

 of San Francisco, that mosquitoes are more abundant 

 about well watered lawns than in vacant lots, with the 

 dry, sandy surface which they naturally have in a dry 

 summer season. But there is not the slightest evidence 



