EXPERIMENTS ON CHINCH BUGS. 
By Pror. S. A. FORBES. 
MEMORANDA OF EXPERIMENTS RELATING TO USE OF KEROSENE 
EMULSIONS ON CHINCH BUGS. 
Solutions with which dilutions were made.—(1) Soap suds, 1 pound 
soap to 10 gallons water; (2) soap suds, 1 pound soap to 20 gallons 
water; (3) potash, 1 pound to 50 gallons water. 
EMULSIONS AS DILUTED. 
QUI OOne 
Per cent. of 
kerosene. 
2 parts kerosene, 1 part milk, 45 parts water.......----.---.-.--..-----about 4 
iGparopxerosene, part milk; 18’ parts water... 2... .--22.s--2-- tscises -- osc ees 5 
ispart kerosene, Uspart‘miuk, 18' parts solution 1 s2--.- -.-2.-2s25---5 .. se<e <= 5 
ispanukerosene, | part milk, 38 parts solution 2)--..2.-225.5-=-.--.2.-<--5--- 24 
aigpato Kerosene, 1) part milk, 38° parts water’:\..).2- 2.50 sslet Sone niece seek ee 
. 1 part kerosene, 1 part milk, 38 parts solution 3. Evel Sawa hist kts 24 
. 1 part kerosene, 1 part milk, 30 parts solution 2........ -............. about 3 
On the 22d of July I transplanted several hills of corns to the Jabora- 
tory, placing them in boxes about a foot and a half wide by two feet in 
length. The corn was from two to three feet in height at this time. 
Each hill was infested with several hundred chinch bugs, which were 
of various sizes, below the pupa stage. All the corn was watered once 
immediately after transplanting, and bore the removal well. It was 
kept under shelter, but in the well-lighted dome of the building, and 
fully exposed to the air. 
Experiment 1, July 22, 9 p. m—Applied to a single hill from half a 
pint to a pint of emulsion A, throwing it with a small syringe upon 
the bases of the stalks and suvinees of the ground. For a check upon 
this experiment, I applied water to another hill in the same quantity 
and in the same way... July 23, 9 a. m., the bugs on the first hill were 
still alive, but torpid. July 24, at 11 a. m., about one-fifth of the bugs 
were completely dead; the others were still alive, but most of them 
torpid. July 26, 3 p. m., thirty of the bugs were alive and back upon 
the stalks, apparently uninjured, but all the remainder were dead. 
July 27,10 a. m., the hill was in the same condition. Treated again 
with emulsion B, on the 28th, when all the bugs were killed. Those on 
the hill to which water was applied were not injured in the least, but 
all were back again upon the-stalks in twenty-four hours. 
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