The River must be watched, however, each season until the proposed sewer has been installed, and the water rendered fit to support the fish life, and if serious mosquito breeding occurs there, the stream must be flushed or oiled. The two kinds of mosquitoes which transmit malaria usually breed in fresh, clear water, particularly in the grassy margins of springs and slow-running streams. They fly only short distances, bite after dark, and occasionally enter dwelling houses. From the observations gathered through a period of fourteen years, it seems certain that Beaver swamp is the most prolific source of malarial mosquitoes around New Haven. Undoubtedlv malarial mosquitoes breed in many other regions about the city, but in small numbers when compared with Beaver swamp.
Eternal vigilance is the price of freedom from malaria and from mosqitoes.
Though the major portion of this discourse concerns mosquitoes, I wish to speak of the fly nuisance, which like the mosquito plague, is not only a serious annoyance but also a menace to health. That flies by their habits of breeding in filth and visiting filth, and then crawling over human food, have been responsible for many epidemics of typhoid, cholera and other enteric diseases, has been proven many times during the past twenty years. Special attention should be given to the wastes from military and construction camps. Horse manure may now be handled so that it will not supply the community with swarms of flies. It may be removed daily or at least weekly and spread upon the land.