-49- 
Stomoxys ca lei trans (L.), the steblefly 
The Maryland Agricultural Experiment Station ( 19Q- ) in 1935 
reporter! that progress had been made on the general insecticidal 
project in the study of pine oils, pyrethrum, and rotenone as repel- 
lents. 
Cory, Harns, end Anderson ( 63 ) in 1936 reported that pyrethrum 
and derris dusts had little or no repellent action under conditions 
of forceful tropism, and that the protection given cattle by 
pyrethrum and derris dusts was obtained through the toxic action of 
the materials. The steblefly was more susceptible to toxic action 
of pyrethrum and derris dusts than the housefly. Pine oil increased 
the toxic acticm of the derris -dusts, Hiich have a relatively low 
initial toxic rating. Pyrethrum-impregnated dusts afforded more 
protection per unit cost, then the derris-impregneted dusts, but the 
derris-impregnated dusts ^ere more toxic per unit. 
E. W. Leake, of the Dallas, Tex., laboratory of the Bureau 
of Entomology and Plent Quarantine, United States Department of 
Agriculture, in a typewritten report in 1936 to the Division of 
Insects Affecting ^an and Animals, steted that oowdered cube root, 
rotenone concentrate, and many other materials were ineffective as 
repellents. 
Doty (76) in 1937 reported on insecticidal tests conducted on both 
wild end reared Stomoxys flies by the Feet-Grady method, using ali- 
phatic thiocyanete (Le thane 384), pyrethrum, and rotenone sprays. 
These flies were found to be considerably less resistent than house- 
flies. Pield and leboratory repellency tests showed that Stomoxys 
flies were repelled by these sprays to about the seme extent as ere 
houseflies; therefore, dete obtained from repellency tests on house- 
flies with these materials are. also applicable to the Stomoxys . 
Mycetophilidae 
Lycorie pusille (Meig.) 
An anonymous (6) writer in 1937 stated that derris was inef- 
fective. 
Lycoria praecox Meig. 
Symes ( 269 ) in 1921 reported • that pure derris powder applied to 
a bed of mushrooms infested with the mushroom fly cleared the bed of 
insects in 2 or 3 days, but had no effect on Hyoomyces fungi. It 
was concluded that mushrooms will not stand treatment ,-, ith powder 
insecticides (such as pyrethrum, derris, end 1-percent pared ichloro- 
benzene) . ^"hen not checked in their growth by these powders, the 
mushrooms m ere rendered absolutely unfit for market. 
l ycoria sp. 
Ihomes (272) in 1934 tested, derris egainst mushroom insects. 
