RESULTS OF EXPERIMENTS AGAINST THE CHICKEN MITE. 
Table 1 indicates that several well-known contact insecticides used 
at strengths ordinarily efficient against most sucking and some 
chewing insects proved inefficient against the chicken mite. 
In a number of tests, sodium hypochlorite at a dilution weaker than 
0.94 per cent ("available chlorine") was in all cases inefficient. 
Formaldehyde, 4 per cent, did not give a killing that could be 
termed efficient and was objectionable to the operators. 
Lime-sulphur and sodium sulphur, well-known acaricides, proved 
inefficient, the former even at dormant orchard strength. 
Free nicotine at a strength of 0.07 per cent in combination with 
whale-oil soap, 4 pounds to 100 gallons, proved but slightly efficient, 
while at a strength of 0.12 per cent with a similar proportion of whale- 
oil soap it was moderately efficient. 
Extract of derris, 16 per cent, diluted to 1 to 1,000 and 1 to 500, 
with the addition of whale-oil soap, 4 pounds per 100 gallons, was 
inefficient. 
Whale-oil soap, 1 pound to 1 gallon and at twice this strength, 
showed some efficiency but was hardly satisfactory. 
OILS. 
Tests were made with three types of oil preparations: (1) Straight 
oils, (2) mechanical mixtures of two oils or solutions of another type 
of substance (e. g., naphthalene) in an oil, and (3) oil emulsions. 
Preparations of the first type included kerosene, gasoline, and 
coal-tar creosote oil. Pure kerosene was used in three chicken 
houses. In one house it was efficient; in the two others only moder- 
ately so. Gasoline was of little value. A coal-tar creosote oil (sp. 
gr. 1.062 at 30° C.) was quite efficient. It appears certain that all 
the heavier oils, undiluted, would be efficient, but the lighter oils, 
perhaps owing to too rapid evaporation, are less efficient. 
The tests made with mechanical mixtures are given in Table 2. 
Table 2. — Results of testt 
with oi 
I mixtures and mixed oils against the chicken mite. 
No. 
of 
test. 
Materials. 
Strength. Dilution. 1 Result. 
1 
Paradichlorobenzene 
do 
do 
Per cent. 
100.0 
100.0 
100.0 
100.0 
100.0 
100.0 
100.0 
100.0 
100.0 
100.0 
20.0 
80.0 
86.8 
13.2 
50.0 
50.0 
33.3 
66.7 
25.0 
75.0 
20.0 
80.0 
10.0 
90.0 
7.0 
93.0 
Moderately efficient. 
Somewhat efficient. 
2 
3 
480 grams in kerosene 4§ gallons 
960 grams in gasoline 4J-"gallons 
4 
Naphthalene 
960 grams in kerosene 5 gallons ' Somewhat efficient. 
5 
do 
do 
Do. 
Do. 
Efficient. 
6 
240 grams in gasoline 2 gallons 
7 
Wood creosote oil 
Phenol 
8 
do 
Moderately efficient. 
Efficient. 
9 
Crude carbolic acid 
do 
1 to 9 in whitewash 
10 
1 to 11£ and 1 to 15 in whitewash 
[None 
Inefficient. 
11 
(Kerosene 
Efficient. 
}....do 
}....do 
\....do 
12 
fCoal-tar creosote oils 
\ Phenols 
Do. 
13 
\ Kerosene 
Do. 
f Carbolineum 
/ 
I. ...do 
fCarbolineum 
\ Kerosene 
y.....do 
16 
Do. 
/ 
}....do 
}....do 
17 
/Carbolineum 
Do. 
fCarbolineum 
Somewhat efficient. 
In tests 1 to 6, inclusive, the paradichlorobenzene and the naphthalene were dissolved in the oils. 
