-57- 
Field ( 88 ) in 1926 reported that the derris product Kurmsnge, 
1 ounce to an imperial quart of water, killed 86 percent of Hypo- 
derma larvae,, and at 2 ounces per quart it killed 95 percent. Cat- 
tle dressed with Kurmenge suffered no injurious effect. ' 
Blieck end Beudet (33) in 1927 reviewed the ^ork of Bishopp et 
al. (29) on derris against ox warbles. 
Leynen ( 180 ) in 1928 reported that the "Commission Hollandaise 
du Varron" recommended the use of derris powder for destroying 
Hy p oder ma. larvae, as recommended "by Bishopp et el. (29) in 1926. 
Lietcalf and Flint ( 202 ) in 1928 recommended derris es a wash 
for killing ox war Dies in the hacks of cattle. 
C. H. Richardson (238) in 1928, in a review of isecticides, 
stated that derris had given excellent results in the control of 
cattle grubs. 
Werburton (306) in 1929 referred to the action of the Leather- 
sellers' Company in appointing a committee to consider the whole 
question of the warble fly on cattle, and. this committee' s recom- 
mendation of a derris soep wash, consisting of 1 pound of pondered 
d.erris root, 1/4 pound of soft soap, end 1 imperial gallon of water. 
G-aut (_99_) in 1929 outlined a. plan to kill all warbles in cattle 
within a given area of Worcestershire County, England, by the use ? 
of e wash made according to the following f ormule : Stendardized 
derris powder, 1 pound; soft soap, 1/4 pound; and ^eter, 1 imperial 
gellon. 
Geut end ir alton (103, 104 ) in 1929 reported that the use of a 
derris- sopp wash made according— to-a formula recommended by Bishopp/ S ave 
et al. /pronounced success against ox warbles end ^es, moreover, a 
■fool-proof remedy. It was made up es follows; Polvo (derris powder) 
1 pound, soft soep 1/4 pound, water 1 imperial gellon. The soft' 
soep was boiled in about 1 quart of water. After cooling somewhat 
it wes gradually poured on the dry powder thet hed been previously 
placed in e smell bucket or cen, end mixed by means of a wooden 
stirrer into the consistency of mud; enough cold water was then 
added to make up 1 gellon of wash. It was ap-nlied ^ith a soft 
cloth, netting the warble lumps thoroughly. The wash should be 
frequently egiteted to prevent sedimentation. Warble Fly Ointment, 
a derris product made by Cooper, McDougell, and Robertson, Berkhamsted, 
England, gave a 100-percent kill Hien forced into ever 1 - warble hole. 
G-aut (100) in 1930 reporter 1 on experiments with derris against 
the ox warble fly in Worcestershire County, England. The insecticide 
was standardized derris powder (Polvo) , used according to the formxila 
of Bishopp 1 s et al. (30). Replies to a questionnaire ihdiceted that 
232 out of 244 farmers considered thet the derris-soep wash hed been 
satisfactory for killing warbles. Tests in 1930 indicated that a half- 
strength wesh gave 100-percent kill of warbles at each of the 4 eppli- 
cetions. Experiments have proved that both the full-strength and 
half-strength "ashes, used 28 days end 56 days efter preparation, are 
just as effective as freshly made material. 
