50 



Attractiveness tests. Baits were sprinkled into bait stations 

 fashioned of 3.8-1 milk jugs (R. C. Axtel 1 , unpublished data). Bait 

 stations were placed in a 1.8 by 1.8 by 3.7 m screened enclosure into 

 which 200 five-day-old female house flies had been released. The 

 enclosure was in full sun but baits were protected from sun and rain 

 by a small structure inside the enclosure. Mortality was recorded 

 after 2k hr. 

 Topical Application of Insecticides to House Fly Adults 



Stock solutions were made by placing 1 g of the active ingredients 

 (Al) of the insecticide in 100-ml volumetric flasks and adding enough 

 acetone to bring the volumes up to 100 ml. Test concentrations were 

 made in acetone from serial dilutions of the stock solutions. 



Before use, all glassware was washed in a detergent and rinsed 

 thoroughly with water. When dry, three final rinses of acetone were 

 applied and glassware was baked in an oven at 176.7 C for 2k hr. 



Laboratory colony house flies, 3 to 5 days old, were immobilized 



with a vacuum and males discarded. While immobilized, female f lies 



TM 

 were dosed with test concentrations using a 10-ul Hamilton syringe 



TM 



equipped with a Hamilton repeating dispenser. Flies were released 



into cylindrical cages, 12 cm high by 7 cm in diameter. Cotton balls 

 saturated v/ith a sucrose solution were placed on the tops of cages as 

 a food source. 



Tests were performed at 26.1 C and ambient humidity. Mortality 

 was recorded after 2k hr. Criterion for death was total cessation of 

 movement. 



