398 ECONOMIC ZOOLOGY AND ENTOMOLOGY 



Although the actual damage done by these insects is not 

 often very great, they are, on account of their unpleasant odor 

 and their habit of crawling into everything, most disgusting 

 creatures to have about the house. It is suspected that they 

 may be concerned in the transmission of certain diseases by 

 contaminating food. Fumigation with hydrocyanic gas is 

 the best remedy to use when this is practicable. There are 

 many roach powders on the market, but few of them are 

 wholly satisfactory. Indeed it is usually only by a combina- 

 tion of several methods of fighting, such as poisoning, trap- 

 ping and sealing up their hiding places, that one can hope to 

 control the roaches in a badly infested house, unless fumiga- 

 tion is resorted to. All the cracks and crevices where the 

 roaches hide should be filled if possible; when this cannot be 

 done such places should be thoroughly syringed with a solution 

 of bichloride of mercury. Sweet chocolate or sugar and pow- 

 dered borax thoroughly ground together make a very good 

 poison. It is most readily eaten from pieces of slightly 

 moistened bread. Phosphorous paste makes a good poison 

 when spread on moist bread. Many roaches may be trapped 

 by placing food or some other attractive article in the bot- 

 tom of a deep vessel and arranging sticks or papers so the in- 

 sects can easily crawl from the floor to the edge of the vessel. 

 The sides of the vessel should be steep enough so the roaches 

 cannot crawl out after they have entered it. 



Ants. In the southern states a few of the common ants 

 may become of some importance in the field or garden on ac- 

 count of their habit of making large bare areas around their 

 nests or because they strip the foliage from plants. The 

 introduced Argentine ants, Iridomyrmex humilis, are the 

 worst of these, as they do considerable damage to citrus and 

 other trees by destroying the opening blossoms or the very 

 young fruit. In badly infested regions almost all kinds of 

 flowers are attacked. All kinds of stored food products may 

 be infested by these ants and the loss in store rooms from this 

 source is often important. But it is as household pests that 

 ants are of primary interest. One little red species, Mono- 

 morium pharaonis, makes its home in houses, building nests 



