MOSQUITOES AND ANTS 301 
The entire life round requires only ten days to two weeks under favor- 
able circumstances. 
Any thorough effort at control is best directed toward destroying 
the breeding places or preventing the insect from breeding in such as 
cannot be destroyed. The latter may be accomplished by pouring oil 
on the water, so as to prevent the larve from reaching the air when 
they come up to breathe. Large tanks above ground may be screened. 
In a word, stagnant water must be eliminated, or mosquitoes kept 
from it. In addition careful screening of houses is highly desirable, 
especially since some diseases are carried by certain species. 
In clearing a room of mosquitoes a fairly satisfactory substance is 
available in pyrethrum, or ‘ Persian insect powder.’ This may be 
heaped up in little piles on a pan and lighted; or, better, it may be 
poured out on a piece of tin or a pan set over a kerosene lamp. In 
the latter case not much smoke is given off, but the volatile oil that 
stupifies the insect permeates the air. 
Another and successful fumigant consists of 1 part of saltpeter 
mixed with 3 parts of powdered jimson weed, and burned on a tin pan. 
Eight ounces to 1000 cubic feet is sufficient. 
House Ants 
The commonest ants in houses are the “ little red ant,’ Wonomorium 
pharaonts L., and a closely related species, somewhat larger and black 
in color, Wonomortin minutum Mayr. 
In getting rid of ants it is a great help if the main colonies can be 
hunted out and destroyed. The black ant lives outdoors, and enters 
the house through some convenient crack. The little red ant always 
has its nest in the walls or under the floors. 
Either may be caught and Killed in large numbers by saturating a 
sponge with sweetened water, placing it where they are abundant, and 
now and then dropping the sponge into boiling water. Scraps of bone 
or meat will do as well, and should be burned when well covered. 
A successful method of fighting ants has recently been devised in 
California in the warfare against the notorious Argentine Ant (Jrv- 
domyrmex humilis Mayr.), which overruns dwellings, stores, and ware- 
