216 SCHOOL ENTOMOLOGY 



Equal parts of chocolate and borax scattered in the 

 haunts of the roaches is claimed to be one of the best means of 

 destroying them. Badly infested buildings should be fumi 

 gated with hydrocyanic acid gas (see p. 336). Much may 

 be done by a thorough cleaning of the premises and then stop 

 ping up all cracks and crevices which furnish them shelter. 

 Rooms may also be fumigated by burning pyrethrum powder 

 powder as suggested for flies and mosquitoes (p. 178). An 

 ingenious method of destroying roaches used in Australia 

 is by placing a saucer of flour 3 or 4 parts, and plaster of 

 Paris, 1 part, where the roaches may feed on it and near by 

 a saucer of water, both being supplied with bridges of card- 

 board or sticks to give easy access. The roaches feed on the 

 mixture and when they become thirsty and drink the plas- 

 ter sets in the intestines and causes death. Phosphorus 

 paste, obtainable at drug stores, if spread thinly on bits of 

 card or paper and placed in the runways of the roaches will 

 destroy many of them, but should not be left where domestic 

 animals or children may be affected. 



129. House Ants * (33). Several species of ants are 

 common household pests, where they are usually more of a 

 nuisance than the cause of much real damage. They are 

 all social species with the general habits described on 

 page 152. 



The Little Red Ant f is the most common species and is 

 practically cosmopolitan in its distribution. It very com- 

 monly makes its nests in the walls of houses or beneath the 

 floors where they are difficult to eradicate. Owing to its 

 small size, being only about one-twelfth of an inch long, it 

 is able to go through very small openings, but only by fol- 

 lowing the workers may the nests be located and if perma- 

 nent relief is to be secured the nests must be destroyed. 



* Family Formicidce, see page 152. f Monomorium pharaonis Linn. 



