HOUSEHOLD AND CAMP INSECTS 37 



The dusting of places haunted by fleas with sodium fluoride, a 

 comparatively new insecticide, is suggested as a promising method 

 of destroying these insects, since it has given very good results with 

 both cockroaches and ants. 



The washing of walls and floors o infested buildings with an 

 emulsion consisting of crude oil 80 per cent and whale oil soap 20 

 per cent, diluted with 9 parts of water, destroys all stages, can be 

 applied with safety and is readily washed from the floor. A gallon 

 is sufficient for a room 12 by 12 feet. 92 



Two ounces of cresol, if properly vaporized, produces a grayish 

 vapor highly poisonous to fleas, though not offensive or injurious to 

 man or domestic animals. The room should be kept closed until 

 the vapor disappears. Burning cresol produces a dense black smoke 

 harmless to the insects, and this should be avoided. 93 



Infested ships or buildings, where practicable, may also be treated 

 with Clayton gas, burning sulphur or hydrocyanic acid gas, all well- 

 known and very efficient insecticides. 



General infestations by fleas usually originate in some dusty, 

 undisturbed shelter, and the first step should be to ascertain these 

 localities and stop breeding by thorough cleaning, or treatment with 

 one of the above-mentioned materials. In the case of infested yards 

 or lawns, all rubbish underneath the building should be removed 

 and burned, and the surface of the ground dressed with lime, sul- 

 phur or sprayed with an insecticide. The grass of the lawn should 

 be cut as close to the ground as possible, the trimmings burned, and 

 the lawn kept well watered. The elimination of dry dust and an 

 abundance of moisture are very detrimental to fleas. 



Cases occur in the southern and west central United States in 

 which pigs appear to be the source of serious flea infestations, due 

 in many instances to their having free run under buildings. Fleas 

 may be destroyed on pigs by dipping the animals in a creosote bath, 

 or by sprinkling them with crude petroleum during feeding times. 94 

 They should be prevented from sheltering under buildings, and the 

 infested ground treated as described above. 



02 Tackson. Jour. St. Med. London, 24 -.277-^4. 1916. 



93 Lane. Ind. Med. Gaz., 1:104-5. 191=;. 



94 Bishopp. U. S. Dep't Agr. Farmers Bui. 683. 1915. 



