106 
commenced to loosen at tlie margins and cuil upwards. At 
on the following morning a single example only was found capai 
of slight motion. 
Experiment 2.—This was a repetition of the first experiment wi 
identical results except that all the plant lice examined on 1 
morning of the 19th were absolutely dead. 
Experiment 8. -In this case the same solution was applied to 
infested leaf with a camel’s hair brush with the same effects, all t 
bark lice being dead at eight the following morning. 
Experiment 4.—On the 22d of the month a two and a half ] 
cent, dilution of the kerosene emulsion was thrown with a foi 
pump and a tubular nozzle upon a branch of a soft maple ti 
The leaves wnre not as thoroughly wetted as desirable. 1 oui dt 
after about half the young bark lice were alive, although it is p 
sible that the branch treated had been restocked, by young fr< 
other parts of the tree, as the insects were still moving about and 
precaution had been taken to prevent such migration. 
Experiment 5.—On the same day a branch of soft maple attacl 
to the tree was dipped in a two and a half per cent, dilution 
kerosene, and on the following day three-fourths of the bark 1 
were dead. Four days after a few were still alive, but not enoi 
to do any appreciable harm, and another application would don 
less have killed them all. 
Experiment 6.—On the 29th the same experiment was tried w 
a five per cent, dilution of kerosene, the emulsion being made v 
whale oil soap, and common soap suds being used for dilution. 1 
days later the bark lice remaining on the leaves of this branch were 
dead. 
Experiment 7.—On the 29th, on the other hand, an applicat 
was made to a branch by dipping in a two and a half per C( 
dilution, soap suds being again used as the diluent, and five d 
thereafter no considerable diminution in the number of living b 
lice was apparent. It seems likely, however, considering the len 
of time that had elapsed between the experiment and the ohsei 
tion, that the branch had been restocked by young from other p, 
of the tree, as the lice were still actively crawling about. 
Experiment 8.—On the 81st of the month the leaves of a bra 
of soft maple which was stocked with young bark lice were dip 
in a five per cent, dilution of kerosene emulsion like that use* 
the preceding experiment. Five days later a few living bark 
still occurred upon the leaves, but nearly all had disappeared. 
Experiment 9.—On the 6th August a similar experiment 
made with a similar fluid, but containing ten per cent, of keros' 
The branch treated was not examined until nine days afterwa 
The leaves were not at all injured by a solution of this stren 
Many bark lice still remained upon them, but they had perl 
been restocked with living young. 
In all the preceding observations the effect upon this bark 
was determined by microscopic examination, the sign of death n 
