The =Pine Sawfly= (_Lophyrus Pini_).—Fortunately, this insect is not abundant in the British Isles, though on the Continent the damage it does in the pine forests is by no means inconsiderable. The insect may readily be recognized by its wide, flattish body, and usually dark appearance. Having attained to full size in the trees, they form cocoons among the foliage or on the stems, and remain in this condition until the following spring, when, in April or May, the perfect insects make their appearance. The male is considerably smaller than the female, while the full-grown caterpillar, which is of a greenish-yellow colour, with a row of black spots on either side, is about an inch long. The remedial measures are not at all easy, especially when a large number of trees are attacked, but single specimens may be entirely cleared by shaking the caterpillars into a sheet placed beneath the tree. [Illustration: (_a_) WILLOW BEETLE (_Phyllodecta vulgatissima_), AND (_b_) ITS LARVA.] The =Larch Aphis= (_Adelgis laricis_) and =Giant Sirex= (_Sirex gigas_) are both, more or less, harmful to the larch. The latter is a formidable and splendid insect, which is, however, not very abundant in this country. Generally felled trees, or such as are somewhat sickly, are chosen by the female in which to lay her eggs. These are deposited beneath the bark by means of the powerful ovipositor, and in course of time the whitish cylindrical maggots make an appearance, and with their strong jaws form large borings in the affected tree. Cutting down and burning infested trees is the only practical remedy. The =Willow Beetle= (_Phyllodecta vulgatissima_) causes considerable damage to osier plantations, and would appear to be greatly on the increase of late years. Much damage has been done to osier holts in various parts of the country, and in northern Ireland the ravages of this beetle were particularly noticeable during the past five years. The insect, which is metallic green or blue in colour, passes the winter in the adult state, at which time it may be found amongst refuse of the osier beds, such as the heaps of bark, and also at the base of old stools and beneath stones or other shelter. The larvæ have a tough yellowish cuticle with conspicuous brown bristles, the head and prothorax being black and hard. The eggs are laid on the undersides of the leaves in spring, and when the larvæ are hatched they feed on the leaves, eating holes quite through to the upper surface. Burning all rubbish in the osier beds is to be recommended, and spraying with Paris green or lead arsenate has been found useful.