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Chemische Fabrik ^arienfelde are effective against mange mites on cattle. The 
rotenone contained in the derris root is very effective against mites, alth" u -':. 
the other ingredients of the root also have a certain out considerably inferior 
effect; therefore, the manufacture of the preparations should be standardized 
to guarantee a certain percentage of rotenone. In the control of insects en 
animals covered with a more or less dense coat of hair, the amplication 
soueous solutions with en addition of 2.5 percent of green soan is preferred, 
whereas, in human medicine oily solutions appear to he more favorable'. In si 
infestations a single application is sufficient. On the other hand, in feevere 
infestations several applications, made at 8^day intervals, rill be required, 
according to the severity of the case. 
Lesser (92) in 1940 wrote that in Japan a 2. 5-percent emulsion of bromc— 
rotenone was v >re^ared, using gum arable, and was anplied to the entire body, 
except the head and neck, of 20 patients with scabies. After 3 or 4 ap] lications 
10 patients were completely cured, although some of them had been unrelieved 
by various sulfur treatments. Of the others, 9 were relieved and 1 failed to 
complete the treatments. One patented dermal parasiticide contains rotenone as 
the active agent, 
Tarsonemidae 
H em iter son emus latus (Banks), the broad mite 
G-onggrijp (66) in 1929 reported comparative tests with sulfur, akar toela 
extract -prepared by the Deli Proefstation te Medan, Sumatra, and Neoton against 
mites, ( Tersonemus translucens ) He mi tarsonemus latus (Banks), on young rubber 
trees in a nursery. The Neoton was used at the rate of 22.5 gm. , added to a 
solution of 45 gm. of soft soap dissolved in 700 cc. of water at 60° C. This 
,n ss stirred to a homogeneous emulsion and then diluted to 18 liters for spraying 
upon the trees. The derris -preparations appeared to kill mites only by aetual 
contact, but the effect of sulfur is attributed to the formation of volatile 
sulfur compounds. Sulfur gave the best and. quickest results at one-third to 
one-fourth of the cost of the other materials. 
Ta rsonemus pellidus Banks, the cyclamen mite 
The Ohio Agricultural Experiment Station ( 116 ) in 1934 reported, that 
Hotecide used at the rate of 1:400 on begonia slants gave good results in the 
control of the cyclamen mite. Flower production was increased more than 100 
percent on the treated plots, as compared with the checks. 
T arsonemus sp. 
The Pennsylvania Agricultural Experiment Station (120) in 1938 reported 
that these mites '"ere not controlled by pyrethrum and derris dusts and sprays. 
Tetranychidae 
Bryobia praetiose Koch, the clover mite 
Andries (5) in 1932 recommended Perrisol at 1:800 as a. summer spray against 
