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NBHATODA 
Anguillulidae 
Anguilluline dipsaci s Dlpylenohua dipsaol filiplus (Kuhn) Filipjev, the 
ffigg wiww — 
A single application of 10 liters of water containing 2 percent of 
"Guesarol" and 0.2 percent of Tinopol oil per square meter is very effec- 
tive in sterilizing eelworm-infested soil. Guesarol is a powder contain- 
ing 5 percent of DDT.— Geigy Colour Co., T td. (166) . 
THYSANURA 
Lepismatidae 
Lepisma saccharina L., the silverfish 
Spraying with refined odorless kerosene containing 5 percent of DDT 
killed silverfish in a wheat-sample room and the first floor of a flour 
mill, and the residual effect of the spray caused the death of invading 
silverfish for many weeks after treatment. In another test, two 100-pound 
cotton hags, one treated by dipping in a 5-percent solution of DDT in 
carbon tetrachloride and the other untreated, were filled with flour and 
stored next to each other in a mill basement. In a few hours the untreat- 
ed bag was literally covered with silverfish, while not a single insect 
was observed on the treated bag.— Cotton et al. (120) • 
DDT residues in buildings sprayed with kerosene-benzene solutions 
containing 3, 4, or 5 percent of DDT killed silverfish.— Ross (306) . 
Tests on silverfish have not been satisfactory in experiments where 
conditions have not been well controlled.— N. J. Agr. Expt. Sta. (2 75 ). 
Silverfish succumbed to Gesarol A-3 dust when their runways and 
trails were dusted.— Parker (287 ) • 
Thermobia domestic v?ack., the firebrat 
Deobase sprays containing 0.2 percent of DDT, together with pyrethrum 
or other paralytic agent as used for houseflies, gave excellent control of 
