19 - 
Fulrnek (35) in 1925 gave directions for spraying against leaf lice 
with derris. The formula is 1 kilogram of akar tulDa (derris), 100 liters of 
water, and 300 grams of soap« 
Hartikawa (43) in 1925 reported tests made in Japan with " tuba- fluid" , 
a whitish solution made from derris roots supplied "by an insecticide dealer. 
The method of preparation vyas unknown to the author. The author tested 
this solution on various insects and foiond that it v/as particularly effective 
against the larvae of the rush sawfly. The tu"ba fluid, diluted v/ith 1,000 
times its volume of water, killed 100 percent of the larvae. Parallel 
eicrperiments made with the tul^a fluid diluted with soap water showed that 
there is practically no different in effectiveness "between the solution 
diluted with water alone and that diluted with soap water. 
The Michigan Agricultural Experiment Station (69) in 1925 reported 
that derris sprays had given encouraging but not conclusive results against 
the "black cherr;,- aphid and various apple aphids. 
Otanes (7^) in 1925 wrote that in certain parts of the "Visayan 
Islands, as in Ce'bu, it is said that farmers sometimes use the roots of 
Derri s (species uniaiovm) for combating the rice borer, by scattering 
chips of the roots and stem. The Juice nixes in solution v/ith the 
water, and v;hen the caterpillars come in contact v/ith the water, as 
when the;- transfer from stalk to stalk or after hatching, they get 
poisoned and soon die. Just how effective this remedy is "nas not been 
scientifically determined. If this poison will really kill the rico 
borer it v.'ould probably be equally effective against the rice case-worm, 
Hyraphvil a doi3unc talis . 
K, M, Smith (85) in 1925 reported on the control of certain 
mag£;ots attacking the roots of vegetables. Tests wore made with 
various insecticides for the control of the onion fly, Kylom.ya antiqua 
Mcig. , the carrot fly, Psila rosac . , the cabbage root fly, Chortophila 
brassicae Bouche, and the turnip gall weevil, Ceuthorrhynchus pleurostii;jna 
Marsh, A mixture of 1 ounce of derris with 2 ounces of soot per square 
yard did not give results promising enough to justify further trials 
with it, 
Howard (101) in 1925 reported that further investigations had been 
made in the Bureau of Entomolo©^ of insecticides derived from derris. 
l.IcBride (63) in 1925 v/as assigned one of the projects in entomoloa^ 
and economic zoology of the Minnesota Agricultural Experiment Station 
entitled "A stud;^-- of derris and related insecticides for the control 
of external parasites of domesticated animals", but no report of v/ork 
under this project was published. 
UBRARY 
OTATE PLANT BOARD 
