124 AGRICULTURAL EXPERIMENT STATION. 



any one who attempts to conduct a mosquito campaign to know 

 that the real danger spots are aimed at. Indiscriminate oiHng of 

 ponds and streams where no mosquitoes are known to breed and 

 wJiere other measures are available in case they do, is bound to 

 raise opposition, increase expense and to fail in obtaining proper 

 results. 



the: woodland swamp mosquito and the malaria carriers. 



These may be dealt with as one, because they usually occur to- 

 gether. The species of Anopheles, however, also occur with the 

 house mosquito, and in almost any place except positivelv foul 

 water they may and do also occur. All the methods suggested 

 under the previous heading will aid in keeping down the malaria 

 carriers. 



Culex syhestris favors swamp areas large or small, and often 

 occurs in low, soft springy land, in holes where water stands. 

 Places of this character are often drainable by a ditch into a nat- 

 ural water course ; indeed the swamp area usually has an outlet 

 through which a slow drainage occurs, and it may only be neces- 

 sary to open a way for the more rapid carrying off the waters. 

 Culex pipiens may also breed in such areas, so they deserve care- 

 ful attention in any case. 



Occasionally it happens that such a depressed area is of consid- 

 erable extent or in a pocket not easy to drain without considera- 

 ble expense. In such a case a small pond may be formed, some- 

 times by a dam, if live water enough comes in to maintain a little 

 flow through it, sometimes bv digging out a pool and using the 

 excavated material to fill at the edges and make a proper bank. 

 In the former case the depth should be great enough to make the 

 water reach a firm edge at all points ; in the latter the pool should 

 be not less than two feet deep with provision in each case for an 

 overflow ; if possible also for. a complete drawing of the water, 

 should that at any time be deemed desirable. A pond or pool of 

 that kind, stocked with almost any small fish will be a safe and 

 pleasant substitute for a dangerous and ugly breeding area. An 

 instance of this sort of work is near Metuchen, on land of Mr. 

 Thomas A. Edison. It is important to have the edges clean and 

 without overgrown shallows, that fish may get in everywhere and 

 no shelter be available for Anopheles. It is equally desirable to 

 have the pond elsewhere sufficiently free from vegetation to allow 

 of the unrestricted movement of fish everywhere. 



The essentials pointed out for the artificial ponds should be 

 carried over to natural ponds and swamp areas that cannot be 



