BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE 57 
In experiments with peas, seeds were soaked in an aqueous solution 
of octamethyl pyrophosphoramide before planting. When the plants 
grown from these seeds were analyzed after 2% months, at the usual 
stage of growth for harvesting peas, the insecticide could be detected 
in peas, pods, and vines. 
Tests utilizing the analytical method which measures the degree 
of inhibition of the enzyme cholinesterase showed that octamethyl 
pyrophosphoramide is converted in the plant to some material which 
lias an inhibitory action many times greater than that of the original 
insecticide, 
A number of other organic phosphorus compounds were submitted 
for preliminary te>ting. Several showed pronounced systemic action, 
among them the oxygen analog of parathion, although parathion 
itself does not have this property. 
Specifications for Aerosol Formulations and Equipment Prepared 
Specifications were prepared for a pyrethrin- containing low-pres- 
sure aerosol formulation and for a formulation containing allethrin 
as an alternate for the pyrethrins. 
Tetraethyl dithiopyrophosphate in aerosols for use against insect 
pests in greenhouses was approved. The quality of the commercial 
grade of this insecticide has been improved to eliminate material in- 
soluble in methyl chloride." Aging tests showed that tetraethyl 
dithiopyrophosphate has less action on aerosol containers than para- 
thion or tetraethyl pyrophosphate. 
Containers and valves proposed for use with -low-pressure aerosols 
by various manufacturer- were tested and evaluated. A purchase 
specification was drafted for a 12-ounce container complete with 
valve. 
Proposed Federal Specifications for Emulsion Concentrates and 
Wettable Powders Drafted 
Proposed specifications were drafted for formulations of several 
new insecticides. They include emulsion concentrates containing 20 
percent of lindane. -15 percent of chlordane, 45 percent of toxaphene, 
23 percent of aldrin. and 18 percent of dieldrin. and water-dispersible 
powders containing 75 percent of DDT, 25 percent of lindane, 25 per- 
cent of aldrin, and 25 percent of dieldrin. 
Preliminary studies indicate that the concentration of the lindane 
water-dispersible powder can be increased to 75 percent without loss 
of its satisfactory physical properties. 
The tentative specification for 75-percent DDT water-dispersible 
power received some minor revisions and was accepted as a Federal 
specification. 
The specification for louse powder also was revised and accepted 
for Federal use. 
Specifications for Botanical Wastes Used as Carriers for Dusts That 
Protect Grain Prepared 
The suitability of several botanical wastes as carriers for insecti- 
cides in dusts to be applied to stored grain was tested in one phase 
