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stocked with goldfish, and the other was left as a feeding 

 ground for ducks. Both were ideal as breeding places for 

 mosquitoes. Where the fish had been introduced mosquito 

 larvse continued to flourish; but soon in the other pond there 

 were no larvse to be found. He then put ten mallard ducks into 

 the fish pond, and within forty-eight hours only a few larvse 

 were left. The following letter commenting on this experience 

 is of interest to all who suffer in summer from a pest of mos- 

 quitoes : 



Corroborating Dr. Dixon's interesting report on the duck as a preven- 

 tative against malaria and yellow fever (Journal, American Medical As- 

 sociation, October 3, 1914, p. 1203), I have been observing the food of the 





v&S&k. ~* 



WOOD DUCK. 



One of the most useful native ducks which destroys mosquitoes. (From Game 

 Birds, Wild Fowl and Shore Birds.) 



wild duck for the past three years, and find that the mosquito and larvae 

 are readily devoured by the duck. I have eight varieties under observa- 

 tion, and note that the best insect destroyers are the beautiful wood ducks 

 (Aix sponsa), and the green-winged teal (Nettion carolinensis) . These 

 ducks are smaller than the mallard (Anas platyrhyncos), and their diet 



