-104- 
contact action of DDT in acetone suspension or Velsicol emulsion was 
much greater than in powder suspensions*— Ross (506) ♦ 
See Pieri3 rapae. — Granovsky (187 ) • 
See Trichoplusia ni.— N. J. Agr. Expt. Sta. (275 ); Tflhite (375 ). 
Lasiocampidae 
Malaco3oma amerioana (F.), the eastern tent caterpillar 
This oaterpillar was effectively controlled with a very snail amount 
of DDT spray (such as 0.1 percent) applied as an emulsion to the egg 
bands or later to the foliage or tents*— Craighead and Brown (125 ) ■ 
La laboratory tests BDT in acetone suspension with Tergitol Penetrant 
7 at the rate of 1 pound per 100 imperial gallons of water was toxio to 
large caterpillars and caused almost immediate cessation of feeding.— 
Ross (506). 
Lymantriidae 
Hemerocampa vetusta (Bdv.), the western tussock moth 
Infested Bartlett pear trees were sprayed with 2.5 quarts of 20-per- 
cent DDT per 100 gallons of water. The control obtained was good, but 
the spray caused a spotted leaf injury.— Borden and Jeppson (94). 
Apple trees infested with immature larvae were treated with DDT, 
with the same results as described for Archips argyrospila .--Borden and 
Jeppson (90). 
Porthetria di6par (L.), the gypsy moth 
Experiments in the aerial application of DDT were conducted at 
Greenfield, Mass., during 1944. Complete control was obtained in a 20-acre 
oak woodland with 5 pounds of 1301 in 5 gallons of solvent per acre, 
applied before the eggs had hatched and before the foliage appeared. 
Later tests with the same dosage killed all the second- and third-stage 
larvae in a 5-acre woodland plot. The spray formula consisted of 1 part 
by weight of DDT, 1 part of oyclohexanone, and 7 parts of a light oil. A 
similar formula was used in nearly all subsequent tests, except that 
from 1*5 to 1.8 parts of xylene was substituted for 1 part of oyolo- 
hexanone. The spray settled through the forest canopy to the understory 
as a fine mist, leaving upon evaporation a uniform crystalline deposit 
of DDT on all parts of the trees. At New Haven, Conn., as little as 1/2 
pound of DDT per acre gave good control of last instars of the gypsy 
moth on small plots of low-growing trees.— Craighead and Brown ( 125 ) ; 
Dowden et al. (136). 
