2 



The mosquitoes found on the ceilings of bedrooms in the evening 

 may be quickl}^ and easily killed by means of a small shallow tin cup 

 (such as the lid of a blacking box) nailed to the top of a stick and wet 

 inside with kerosene. This cup is placed over the quiescent mosquito, 

 which immediately drops or flies against the oily surface and is killed. 

 But altogether the most satisfactory means of fighting mosquitoes are 

 those which are directed to the destruction of the larva' or the abolition 

 of breeding places. These measures are not everywhere feasible, but in 

 many places there is absolutely no necessity for the endurance of the 

 mosquito plague. The principal remedies of this class are three : The 

 draining of ponds and marshes, the introduction of fish into hshless 

 pools, and the use of kerosene on the surface of the water. 



The draining of breeding pools needs no discussion. Obviously the 

 drying up of such places will prevent mosquitoes from breeding therein, 

 and the conditions of a successful application of this measure will, it is 

 equally obvious, vary with each case. 



The introduction of fish into fishless ponds is feasible and advisable 

 in many cases where the use of kerosene on the surface of the water 

 would be thought undesirable. In tanks supplying drinking water, for 

 example, fish would destroy the mosquito larvae as fast as hatched. A 

 case is recorded in Insect Life (Vol. IV, p. 223) where carp were 

 emploj'ed in this way with perfect success by an English gentleman 

 living in the Riviera. At San Diego, Tex., the people use for this pur- 

 pose a little fish, called there a perch, the species of which the writer 

 has not been able to ascertain. Probably the common voracious little 

 stickle-back would answer admirably as a mosquito destroyer. 



Probably the best, and certainly the easiest, of wholesale remedies 

 against mosquitoes is the application of kerosene to the surface of 

 breeding pools. The suggestion that kerosene could be used as a remedy 

 for mosquitoes is not new and has been made more than once. Exact 

 experiments out of doors and on a large scale were made in 1892 by the 

 writer. These and subsequent experiments show that approximately 1 

 ounce of kerosene to each 15 square feet of water surface on small pools 

 will effectually destroy all the larva^ and pupa^ in that pool, with the 

 additional advantage that the adult females, not deterred from attempt- 

 ing to oviposit, are killed when they alight on the kerosene-covered water. 

 Ordinarily the application need not be renewed for a month, though 

 var^dng circumstances may require more frequent applications in certain 

 cases. 



Since 1892 several demonstrations, on large and small scales, have 

 been made of the practicability of this method. Under the writer's 

 supervision two localities were rid of mosquitoes by the use of kerosene 

 alone. It will, however, probably not prove feasible to treat in this 

 way the large sea marshes along the coast where mosquitoes breed in 

 hordes, although even here the remedj^ niay prove to be practicable 

 under certain conditions and in certain situations. In inland places, 

 however, where the mosquito suppl}^ is derived from comparatively cir- 

 cumscribed pools, the kerosene remedy will prove most useful. In 

 some California towns, we are informed,, the pit or vault behind water- 

 closets is subject to flushing with water during the irrigation of the 

 land near b3^ A period of several weeks elapses before more water is 

 turned in, and in the meantime the water in the pit grows stagnant and 

 becomes the breeding place of thousands of mosquitoes. Where, as in 

 certain towns and cities, house drainage runs into such a pit and an 



