- 84 - 
cattle and 0.75 and 1.5 percent concentrations caused nearly complete kill 
of all stages. DDT on the same basis failed to kill all of the engorged 
forms at 1.5 percent concentration. The two insecticides were about equal 
in preventing reinfestation. — U. S. Bur. Ent. and Plant iuar. ( 4oc . 
In preliminary tests at Camp Bullis, Texas, against the lone star tick 
dusts, applied at the rate of 1 to 2 pounds of chlordane per acre, were 
superior to DDT dusts applied at the sane rate. A wettable powder and an 
emulsion containing chlordane when applied a6 sprays to infested cattle at 
concentration ranging from 0.25 to 1.5 percent chlordane also proved more 
effective than DDT against the same tick. The two materials, however, ap- 
peared to be about equal on the basis of duration of effectiveness against 
reinfestation.— Knipling (264). 
In tests in Florida chlordane proved promising against the lone star 
tick when applied as a dust to infested areas, and it appeared to be super- 
ior to DDT for this purpose. — Knipling ( 265 ) . 
Dipping dogs in a 0.42 percent technical chlordane emulsion killed all 
ticks except a few engorged females.— Turk andBatt* (4^0) . 
Boorihilus microplue- (Canestr.) 
Four cows were sprayed with a 0.25 percent emulsion of chlordane every 
28 days. No female adult ticks reached maturity on these ccv.-3 although they 
were exposed to heavy larval infestation. — Legg ( 286 ) . 
Dermacentor alb ip ictus (Pack.), the winter tick 
Chlordane shows a distinct superiority over DDT against the winter tick 
on cattle and horses. Nearly complete control of all stages has been ob- 
tained with sprays at concentrations of 0.75 percent chlordane, whereas I 
at 1.5 percent killed only a small percentage of the engorged forms. From 
the standpoint of protection against reinfestation chlordane is also super- 
ior to DDT, At 0.5 and 0.75 percent chlordane prevents reinf estations for 
about two months as compared with ^ne month for DDT at the sane concentra- 
tions. Chlordane as a 5-percer.t cvst has also given good control cf winter 
ticks and proved superior to DDT. — Biahopp and Knipling (34): U. S. Bur. 
Int. and Plant Quar . ( 468 ). 
Dermacentor variabilis (Say), the American dog tick 
Same as fcr Aml'lyom.ma a^ericanuq . — U. S. Bur. Ent. and Plant -vuar . ( 
Derrxirrysgus gallinae (Deg.), the chicken mite 
Dusts containing 2 percent and 5 percent of chl B were dusted into 
a petri dish, mites were placed on the dusted surface, ?r£ the dish was 
covered to prevent their escape. There were no dead mites in the ane 
ter' f 48 hours. — Eixson and Muma ( CI? ) . 
