KEROSENE EMULSIONS ON THE CHINCH BUG. 25 
efficiency of water, soap-suds, and a solution of potash as diluents of 
the emulsion. The first effects were evidently in favor of soap-suds, 
showing that this is at least most prompt in its action. The comparison 
of final effects was interfered with by the fact that about this time the 
bugs on all the hills commenced to die indiscriminately from some cause 
not clearly understood. 
Experiment 10, August 2, 2 p. m.—Applied half a pint of emulsion D 
to the worst hill in the laboratory. August 3, 9.30 a. m., nine-tenths of 
the bugs were dead; the others were scattered on the ground. August 
4,8 a. m., 95 per cent. of the bugs were dead, and the others still torpid 
on the ground. 
Experiment 11, August 2,5 p.m.—Applied one-half pint of emulsion F 
to a hill in the laboratory. At 10 a.m. on the 3d fully 90 per cent. of 
the bugs were dead. 
Additional experiments, which I have not time to detail, showed that 
milk is not necessary to the emulsion, which can be made at least as 
well with soap-suds (1 pound to 10 gallons of water), using equal parts 
of the oil and suds; that a mere mechanical mixture of the simple oil 
and water is effective, and does not injure the corn (at least, in a ratio 
of 5 per cent. of the oil to 95 of water); that all these fluids accomplish 
their purpose when poured on with a sprinkler as well as when applied 
forcibly in a spray, and that they kill the adult bugs as easily as the 
young. 
S. A. FORBES. 
NORMAL, ILL., August 22, 1882. 
