HOUSE ANTS: KINDS AND METHODS OF CONTROL. 2] 
faculty of “getting into” articles of food, particularly sugars, 
sirups, cakes, candies and other sweets, and cooked foods of animal 
crigin. Having once gained access to articles of this sort, the dis- 
covery is at once reported to the colony, and in an incredibly short 
time the premises may be swarming with these unwelcome visitors. 
KINDS OF NORTH AMERICAN HOUSE ANTS. 
The different kinds of North American house ants may be grouped 
on the basis of origin as follows: (1) Tropical Old-World ants, rep- 
resented by 12 species; (2) ants introduced from the New-World 
Tropics, represented by 5 species; (3) native North American ants of 
temperate regions which occasionally inhabit dwelling houses, repre- 
sented by 2 species; and (4) such occasional garden and lawn ants 
as may from time to time become accidental house pests by extending 
their forays into dwelling houses in quest of food, of which 4 native 
North American species are discussed, and also the introduced Euro- 
pean meadow ant. 
INTRODUCED TROPICAL OLD-WORLD ANTS. 
The little red ant,‘ or Pharaoh’s ant (fig. 2), is the best known 
house species. It has attained a thoroughly cosmopolitan distribu- 
tion and has been domesticated so long that it is now difficult to de- 
termine its exact origin, except to place it generally in the Old-World 
Tropics. It was originally a soil ant, nesting out of doors in warm 
countries, and doubtless continues this habit in the tropics of both 
hemispheres. In temperate regions it passes its entire existence in 
heated houses. 
Three other species of the same genus of Old-World tropical ants 
are recorded as having been brought to our shores and as having 
gained foothold, occasionally in dwellings.? None of these species 
have, however, so far established any important record in this coun- 
try as house pests, although they may be expected to appear at any 
time in dwelling houses and other heated structures, particularly in 
the southern United States, and possibly farther north along the 
Atlantic seaboard. One of these, Monomorium salomonis, is stated 
to be the most abundant of North African ants, and to have been 
widely distributed by commerce and to occur in most tropical and 
subtropical countries. A native species of the same genus,? known 
as the little black ant, is referred to elsewhere. 
Two Old-World agricultural or harvester ants* have been brought 
to this country by commerce and are now fairly well established in 
1 Monomorium pharaonis WL. 
2 Monomorium salomonis l., Monomorium destructa Jerdon, and Monomorium floricola 
Jerdon. 
3 Monomorium minimum Buckley. 
4 Solenopsis geminata Fab. subspecies rufa Jerdon and Pheidole megacephala Fab. 
