...of the water, made by the ducks, of course drowned some of the insects — what proportion can not be estimated. For some years I have been using ducks...of mosquito life until the foregoing test was made. Mayflies, stoneflies, and caddisflies also are consumed, usually as larvse. More than 200 caddisfly...

...from any one who has definite data of weights on standard scales. DUCKS VS. MALARIA AND YELLOW FEVER. "For some years I have been using ducks to keep down mosquitoes in swamps that would have been difficult and expensive to drain," says Dr. Samuel G, Dixon. the Pennsylvania Commissioner of Health,...

...24 hours no pupae were to be found and in 48 hours only a few of the larvae survived. He adds : ' ' For some years I have been using ducks to keep down...mosquito life until the foregoing test was made." (Author's Note: There is no doubt that ducks are great destroyers of mosquito life but the foregoing...

...ducks, of course, drowned some of the insects — what proportion can not be estimated. For some years 1 have been using ducks to keep down mosquitoes in swamps...mosquito life until the foregoing test was made.** LEPIDOPTERA (BUTTERFLIES AND MOTHS) When we use the vernacular terms butterflies and moths as equivalents...

...of the water made by the ducks, of course, drowned some of the Insects — what proportion can not be estimated. For some years I have been using ducks...of mosquito life until the foregoing test was made. Beneficial results obtained from increasing the bird population by bird-attraction methods have been...

...must have been drowned, due to the commotion of the water produced by the birds. Doctor Dixon says, "For some years I have been using ducks to keep down mosquitoes in swamps that would have been difficult and expensive to drain, but I never fully appreciated the high degree of efficiency of the...