In a communication from J. W. Robson to the Jo Davies County Horticultural Society, we find some unusually valuable ideas of what will and what will not destroy the oyster shell bark louse, which is such a pest upon our apple trees.

One day, he says, "while cleaning a white-fish barrel, we thought we would try fish brine. Having a young Rawle's Janet apple tree, close at hand, completely covered with lice, we began experimenting, taking a common wooden pail, and filling it with boiling water, dissolving therein one pint of brine. When sufficiently cool to handle, we syringed the infected tree, thoroughly drenching every branch and twig.

Early next spring, on close examination, we found every insect dead and the scale dry and shriveled up ; placed under the lens of a powerful microscope, they presented the appearance of half burnt chips of wood. Other applications since then have proved quite successful.

Those who have made this insect a study, know that the young are hatched about the latter end of May, or first week in June, being earlier or later according as the season is earlier or later. Immediately on issuing from under the scale they commence their upward march toward the ends of the shoots, never making a retro-gade movement unless in case of storms, when they face right about and seek the cover of the old scales. Their ability to move continues only for a few days, when they lose their legs and tails, assuming the scale-like form, and become a fixture of the shoots.

During the last week of May, 1868, the young brood began to move, and in greater numbers than in previous years, so numerous that the shoots appeared to the naked eye as if sprinkled with fine particles of corn meal. Anxious to try the fish-brine cure, we syringed a large tree with two pailsful. It took two minutes by the watch. Result: every louse was killed, and so was every leaf and every green shoot and apple on the tree.

The second mixture tried was half a pint of common salt to a pail of water. Result: the insect lived, but leaves and shoots were destroyed.

The third and last mixture was a quarter of a pound of whale oil soap, dissolved in the same quantity of water. Time expended in syringing, two minutes. Result: death to the insect, health and vigor to the tree, and a handsome and abundant crop.

Before closing we will mention a fact which we noticed last year, which, perhaps, will be interesting to entomologists. While looking at the movements of the young lice through a powerful magnifying glass, we discovered a round shaped, black lady bug, with four distinct white spots on the back, feeding upon the young lice, com-pletely cleaning the shoot as it went along. Farmers, spare every one of them, for they are our best friends.