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Jones (223) In 1938 reported a chenical examination of a sanplc of cu"bo 
root which when received by the Division of Insect. Investigations was found to 
be infested with Dino dcrus "bifovcolatus Well. The whole root and the powder 
nado by the insects were analyze 1 for rotenone with the following results: 
Analysis for rotenone content of two sanplcs >f cube root. 
Sample Percent Rotenone 
Original saiple VThole root 3.3 
Powder formed by insects 1.4 
Specimen sanple of Wholo root 4.1 
original whole root Powder fornod by insects 2.3 
It is seen that the portion of the root through which the insects tun- 
neled, anc 1 which was thus reduced to powder by then, was lower in rotenone 
content than the rcnainder of the root, ^'hat there was no reduction in the 
total rotenone content of the root as a rosv.lt of the insect attack was snown 
by the fact that the net rotenone content of the whole specinon sample, when 
the relative woights of whole root and powder are tai-'en in account, was about 
the sane as that of the original sample of whole root. Thus in a shipment of 
cube root infested by these insects it night be expected, that there would be 
no loss in the total rotenone content provided none of the powdered, material 
was lost. 
Reference to this publication by Jones is nad.o in the Hows Letter (224) 
of the United. States Department of Agriculture, Bureau of Entomology and Plant 
Quarantine, 
Cupples (110) in 1938 stated that soaps containing free alkali or which 
hydrolyzu readily witi: the formation of free alkali cannot be used 'with pyre- 
thru..;, dcrris, or rube, because the active principles f these plants are 
easily decomposed into inert compounds in the presence of alkaline solutions. 
ASSAY CP L01TCH0CA2PUS 
Pozzi-Escot (333,334) in 1935 describe-"', a modification of the carbon 
tetrachloride method of determining rotenone with special reference to its 
application to cube. 
R. J. Prentiss and Company, Inc., (335) in 1935 argued that for the 
evaluation of the insecticidal value oi dusts loss emphasis be placed, on ro- 
tenone content and more on toted, ether extractive. No dcrris or cube powder 
containing less than 15 percent total ether extractives will give satisfactory 
results when used in a dust at the usual dilutions. 
"The situ. tier on cu.be is somewhat similar. There are avail- 
able somewhat limited supplies of what nay be described as high ro- 
tenone cube, which yield powder containing 5 percent or more rotenone 
but as a rule only 15 percent or 16 percent total ether extractives* 
