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    148 Kentucky AgricuZtm·al Emperiméitt Station,
l     i As illustrating the usefulness of this gas for destroy-
   5; ing aphides on other plants I will give here the results of
  '_`v   li, .. ` some experiments on the rose-aphis. This insect appeared
 _-.;,;.;tIji’·l=,?? in large numbers on the terminal iparts of a thrifty
      young bush in my yard last spring and stopped its growth. V
  Hm} I The seriousness of the attack wasnot at first realized, and
  g by Q_i_i.' without intending to make it an object of further experi-
 I “     ment the plant was sprinkled with a watering-can and
,     f_'¥"‘.Q‘ then dusted thoroughly with pyrethrum. This destroyed
Y   i` _`i . yi a good many of the lice, but left others concealed under
Q  ‘_ ` ‘ l-   i the leaves and elsewhere, and the injury was soon under
I   ",_?   way again. On june 2O this bush was sprayed with the
    ; . preparation known as antinonnin, I gram to each quart of
L   ··` lj   Q water. One gallon was applied in the evening. On june
“  I I ’   iiii — 2I the plant lice were greatly reduced in numbers, but a
    *5   good many still occurred on the under sides of the leaves,
I   ryir     · though special pains was taken to reach this surface. The
    yi application was made with a very useful little bucket-
I  ,{     * pump (the "Success’?) made by the Deming Company, of
  `   Salem, Ohio. The antirronnin remained upon the leaves
,‘  ii.; YJ Z,  and proved very injurious to the younger terminal
iiil   '‘_`   growth, so much so that I was obliged to wash it off
y       again by spraying with clear water. On june 22 I noted
  `I   ]_ a good many plant lice on the bush, and it was evi-
  * _ dent that the insecticide, although one of the _, best I
fl  ,`t   ._ have used for such work, could not be depended on to
  *,-4 ~` r> ·,t’ * free the bush from its enemies. On ]une 25 it was decided
_;¥.;,· I   to use the hydrocyanic acid gas, and the bush was en-
`   I .l L. ‘i· _ closed in the tent for the purpose. Under the edge of the
  · ,   _’ tent was slipped a dish containing   fluid ounce of water
  s     and % ounce of sulphuric acid. Then % ounce of cyan-
  _ _ " i QT ide of potassium was added. The fumes of the gas were
  ji ._ kept about the plant ten minutes, when the tent was re-
  ·, V, ‘_ I moved. Every insect was killed. At 8 o’clock the fol-
    " lowing morning the tender growth of leaves and twigs
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