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gra.ni of body weight as compared to 38 micrograms per gram of "body weight 
for DDT, when measured 120 hours after treatment. The corresponding 
values for LD-95 were approximately 25 micrograms per gram of "body weight 
for chlordane and 70 micrograms for DDT per gram of body weight. — Kearns 
et al . ( 2ij-5 ) . 
When chlordane was added to a urea-formaldehyde surface coating (50- 
percent on the dry weight), it was more effective than DDT hut less 
effective than gamma "benzene hexachloride a3 measured both by the time 
to cause 50 percent knockdown and the time to produce 100 percent knock- 
down.— Block Q£). 
See also under Blattella geriaanica . — Gahan §t al,. (l62) . 
The value of chlordane in controlling cockroaches has been demonstrated 
by pest-control operators and others. In general, practical tests have 
shown better results than those in the laboratory.— Knipling (26£)„ 
Chlordane has come into wide use against cockroaches. Its fumigating 
action plays a part in its effectiveness against cockroaches in hiding 
places.— Bishopp ( 32 ). 
The dairy of Oregon State College remained free of cockroaches for 
6 months after the application of a kerosene-chlordane space spray.— 
Fowler (152). 
When tested in a dust chamber where a very small quantity of the 
test material was applied to a surface, a 5-percent chlordane dust killed 
all roaches in 3 days. — Lemmon ( 296 ) . 
Chlordane was recommended as one of the better insecticides for the 
control of roaches by the U. S. Bureau of Entomology and Plant Quarantine 
( ^•72 ) in August 19*19 • Proper application of an insecticide is probably 
more important than the selection of the one to be used. Either powdered 
or liquid formulations will give satisfactory results. 
Gryllidae 
Gryllotaloa hexadactvla Perty, the American mole cricket 
Chlordane was applied to turf as a 5-percent dust at the rate of one 
pound of actural chlordane to the area and watered in. There was an 
average of nine dead mole crickets on each plot of 100 square feet. The 
effectiveness of chlordane against mole crickets persists for as long as 
six weeks to two months after application. Death results from ingestion, 
contact, and fumigation. — Kelsheimer ( 250 . 251 ). 
Acheta assimilis P., the field cricket 
A 5-percent chlordane dust applied at the rate of 1 pound of toxi- 
cant per acre reduced the population about 30 percent within 2M- hours. A 
