Those who undertake for the first time the work of mosquito extermination are confronted with various theories concerning the means by which this important protective measure may be successfully carried out, which are often perplexing. It is quite necessary that these theories should be promptly dealt with, in order that methods which have no practical value may be eliminated from the plan of procedure.
Included among these theories is the widespread belief that birds, fishes, bats, aquatic fowls, etc., render valuable aid in the extermination of the mosquito. Some years ago, it was seriously recommended that certain birds be propagated for this purpose, and more recently this has been suggested in connection with bats. The truth is that the number of mosquitoes devoured by birds and bats has no practical effect in diminishing the danger and annoyance caused by this insect. It is the presence of mosquitoes rather than the