-160- 
Xencpsylla cheopls (Rotsch.), the oriental rat flea 
Chicken houses which were in bad condition and contained much litter 
were heavily infested with rat fleas. The rami was heavily infested 
with rats. One- fourth pound of 3 percent DOT in pyrophyllite per 100 
square feet failed to give results. Repeat tests using 5-percent DDT 
dust gave satisfactory results. A heavy infestation of fleas in a build- 
ing in good oondition was treated with 1/4 pound of 5 percent DDT in talc 
per 100 square feet. There were very few rats present. Control of fleas 
was excellent.--N. J. Agr. Expt. Sta. (275 ) . 
Unidentified fleas 
A 10-percent DDT dust rubbed into the fur of pets constitutes a satis* 
factory primary souroe of control* A 5-percent kerosene spray applied to 
floors, chicken houses and yards, dog kennels, and stable floors is ex- 
tremely effective. Persons have gained relief from flea bites by treat- 
ing the underolothes with a 10-percent TOT dust in talc— Freeborn ( 160 ) . 
At Clemson*, S. C, two basements heavily infested with fleas which 
were spreading up into the house were dusted with a 3-peroent DDT dust 
and complete relief was obtained by the following day.~Cartwright (108). 
A 1-percent DDT-kaolin powder was dusted on sheets of paper on which 
fleas were separately placed and covered with a beaker. Fleas were par- 
tially paralyzed in 11 minutes, totally paralyzed in 40 to 50 minutes, 
and killed in 700 to 740 minutes. —Sen (311 ). 
SCORPIONIDA 
Centruroides liropidus limpidus Karsch 
Young scorpions just after the first molt are easily killed in 24 
hours by a 10-percent DDT powder, and also by a film of DDT on an ordinary 
filter paper. The adults of the same species are dead before 72 hours 
in technical DDT. Khea exposed to treated filter paper, most of the 
adults die about the tenth day.- Vargas and Colorado Iri6 (560) • 
ARANEIDA 
Latrodectus mactans (F.), the black widow spider 
Not affected during 6 days by a deposit of DDT on filter paper.— 
Vargas and Colorado Iris (360) . 
Unidentified spiders 
Examination of the ground under hairy vetch at Oregon City, Oreg., 
disclosed that 5-percent DDT dust had killed spiders. — Rookwood and 
Reeher (303). 
