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was norc saponaceous, and therefore penetrated "better, than that from 
the extract. Dips made with the powder did net keep for more than 
48 hours, a disadvantage owing to the number of animals to be treated, 
whereas those made with the extract kept for up to a week. The addition 
of l/2 pound of soap per 100 U. S. gallons was recommended and also 
that of l/2 pound of sodium carbonate to counteract the hardness of the 
water. For complete control of the parasites, cattle usually required 
two dips, with about a fortnight's interval, twice a year, and sheep 
the same, except when seriously infested, in which case a third pair 
of dips was necessary. 
The effective concentrations of ground root containing 6.8 percent 
of rotenone, and of extract containing 5.5 percent of rotenone were, 
respectively, 1:2000 and 1:10,000 for M. ovinus , 1:3000 and 1:15,000 
^ or —• curystc-rnus, 1:2000 and 1:8000 for K, su i s , and 1:1000 and 
1:6000 for Sa rcopte s spi and psoroptes sp. The ground root and the 
extract were equally effective, and were in no way inferior to other dips. 
In preliminary tests, cube root containing 5 percent of rotenone had 
no effect on the larvae of A nophel es pseudopunctipe nris Theo., after 
15 hours, when used at a concentration at which it killed fish in 30 
minutes. 
Smith and Scales (383) in 1937 reported the results of insecticide 
tests against three cotton insects. 
Tests were planned to compare derris, cube, and devil's shoestring 
containing equal amounts of rotenone in mixtures with sulfur. The mixtures 
were prepared, however, before the analyses were received, and the rotenone 
contents of the mixtures arc only approximately equal. 
Cube containing 4.9 percent of rotenone produced a higher mortality 
of boll weevils than derris containing 3.9 percent of rotenone, Devil's 
shoestring; (1.7 percent of rotenone), or calcium arsenate. The mortality 
from calcium arsenate, however, was higher than that from derris, devil's 
shoestring or mixtures of cube, derris, and devil's shoestring with sulfur. 
Calcium arsenate caused a higher mortality of leaf worms than did either 
derris, cube, or devil's shoestring, used alone or in mixtures with sulfur. 
Res\ilts were as follows: 
