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An anonymous (4) '-riter in 1934 outlined plants for Ontario 
farmers to combat marbles in cattle ^ith^afche derris-soeo -ash. 
In 1932 Stevenson on Berrie Island treated cattle h?v ; nc an average 
of 15 grubs per animal, end as a result of this treatment the 
average number of grubs ner animal fell to three in 1°33. 
According to Bertels (14) a derris suitable for treating c-ttle 
grubs should contain at least 8 percent of rotenone. Good results 
-ere reported in 1934 by the use of Delicia-Dassel'61, a proprietary 
derris product. 
Helraig ( 139) in 1934 reported the results of tests of the fol- 
lowing proprietary derris products against ox rarbles: Derrisol, 
Derris-Vieh^'cschpulver, Abdessol, Rufus Nos. 99, 114, 214, 228, 314, 
Lianol, and Garepetox-Feutan. Abd.assol and Derrisol in 10-percent 
solution gave the best control, namely, 93 to 94 percent. 
Beudet (19) in 1934 reviewed the - T ork of several "-orkers on the 
control of cattle grubs. Peters found that excellent control was 
obtained by the use of a derris suspension -prepared bv soaking 1 kg. 
of finely ground derris in 9 liters of ^ater for 24 hours and then 
adding 250 gm. of green soar: in 1 liter of ^eter. He recommended 
one r-T)olication before the animals ere placed in pasture in the 
soring and a second p police tion in i^py or June. The first amplication 
killed 97.6 percent of the larvae. Remien carried out experiments 
with several proprietary rotenone-containing preparations. One, 
containing ^11 the derris constituents except rotenone, killed 31 
percent of the larvae; 96 to 97-percent control m as obtained "'hen 
the 10 percent of the nonrotenone derris constituents -ere present. 
Derris suspensions prepared the same as those used by Peters killed 
98.6 to 100 percent of the larvae. A rotenone susnension described 
as a "sort of colloidal solution" ™es prepared by dissolving 3 parts 
of rotenone in 20 perts of pyridine, adding 80 parts o^ elcohol, 
and then eddin? this solution to 280 parts of a 2.5 -percent soar 
solution. The rotenone did not settle raoidlv from this suspensi 
'-hen distilled water ^fs used to prepare the solution. This pre- 
paration killed 92 percent of the larvae on cattle "-ashed "-ith it. 
Subcutaneous injection of derris extract in a crlf infested -"ith 
larvae "/as without effect. This res to be expected, as the lervr-e 
are not dependent on the body fluids of the host. Go'tse obtained 
sstisfactor-"- control of the cattle grub with a solution of rotenone 
in soybean oil and also " T ith a suspension of derris in proprietary 
oils prepared by Schering-Kahlbaum. 
Beudet end DeBoer ( 21 , 22 ) in 1934 obteined rood results egeinst 
ox marbles v^ith derris' povder (8 percent rotenone) mixed with 
'•ater 1:30. Rotenone dissolved in acetone and mixed - . ^r 
also yielded good results. Care must be taken tht ell larva 
into contact with the medicament used. 
