The most effectual cure is to syringe the trees affected with a strong decoction of tobacco-water, and the best time to apply it is towards midnight, when they are sure to be upon the upper surface of the leaf, and consequently in a better position to receive the water.

Another of these most destructive insects is the Astyages hemero-biella, but fortunately its visits are more limited than that of the one just noticed. It may make its appearance once, and not be seen again upon the same tree for years to come, or, at all events, in very limited numbers. The caterpillar is of a lightish brown colour, encased in a brown-coloured cylindrical case, from | to 5/8 of an inch in length, from the under end of which the head of the insect is from time to time thrust out. Its mode of attack is very different from that of the Selandria. It attacks the upper surface of the leaf, merely cutting through into the cuticle, when it places its mouth upon the opening thus made, and, erecting itself into a standing position, with its head down and at right angles with the leaf, it feeds upon the parenchyma. In this manner it continues to work until it has made an opening between the upper and under surface of the leaf, when part of its body is introduced, so that it mines out the leaf to a considerable distance round the place of its first entrance. Being of a much larger size than the former one spoken of, it can be easily seen and gathered by the hand; but if they should be in great numbers, the remedy recommended for the Selandria can be applied.

These being the two principal moths or caterpillars with which we are acquainted, we shall refrain from enumerating any of the others, which are described in many other garden works, and shall simply say that we believe the most of those which attack the leaves of the Pear can be destroyed, either by hand-picking, or syringing with tobacco-water. In the case of those, however, which attack the flowers and the eyes of the fruit, the case may be different, and for fuller and more accurate information regarding them I must refer the reader to those works I have already spoken about. We in this country have not nearly so many living enemies to contend with in our Pear-cultivation as several of our neighbours, but what we want in this respect is amply made up to us in the shape of late spring-frosts and easterly winds.

It will be gathered from what has already been said, that a good rich compost is necessary for the Pear. It is a very great mistake to think, as many gentlemen do, that Pears, or in fact any sort of fruit, will do well enough if planted in good garden mould, without any additions being made thereunto. No doubt tolerably good results attend the planting of them in this way in many places, but there can be little doubt that much of the after disappointment and failure of fruit crops is to be attributed to the want of the proper formation of borders. Where tolerable results are obtained without the formation of good new borders, it is an evidence that the Pear suits the locality, and that if new borders on a good principle had been made, fruit of the very highest quality would have been the result. In the making of fruit borders, the first thing to be attended to is the drainage, which ought to be complete; and for this purpose I would recommend a drain of at least 3i feet in depth to be made every 15 to 30 feet, according to the dampness or dryness of the locality. If a fall of 1 in 20 feet can be obtained, so much the better; and these drains should run into a main drain near the box, to be carried off to the nearest place of discharge.

Where the rock is to be got at a depth of 3 or 3 1/2 feet, as we have it here, the drain-tiles may be laid thereupon, and with such for the bottom it is quite unnecessary to concrete or flag in any way; but where a cold deep subsoil exists it would be very advantageous to do so, and place the tiles upon it. Upon this may be added 9 inches of good rough stones, or bricks broken up with a hammer, which will leave about 2 1/2 or 3 feet for the soil. We shall premise that the required quantity of soil has been obtained from a good old pasture, and been put up into a ridge for a few months. The best soil for the Pear is a good rich mellow loam, not too light, but rather inclined to be heavy. This having been obtained, let one load to at least every eight be added of the best stable or farmyard manure, with charcoal or wood ashes in considerable quantities, as well as a good addition of crushed bones, where good fruit is more an object than the expense incurred. Let these all be turned over once or twice to get thoroughly incorporated, after which it may be placed in the border after a layer of green turf has been put therein, to prevent the soil from running at once down through the ruble.

This operation completed, the planting of the trees may be proceeded with at once as already directed; and I may here state that a considerable gain is effected if the trees can be procured and planted about the middle of October, or even earlier, before the leaves fall. In the case of trees, however, which have to come a long distance, this would be impracticable, as they would become heated upon the journey, and consequently much injured.

We now come to speak of the distances which ought to be between the trees at planting. This will depend entirely upon the mode of training and the stock used for grafting. If the Quince has been used, and the trees are intended for pyramids, the distance need not be more than 12 feet, or 15 at the most. If on the Pear stock, the distance ought not to be less than 18 feet if intended for border lines; and if intended for an Orchard plantation even more will be necessary, say from 24 to 30 feet, according to the size they are to be allowed to grow. If the trees are to be planted against the wall, the distances in this case will be regulated by the height of the wall as well as the stock used. For a wall of 8 feet in height the Quince will answer very well, and the trees may be planted every 12 to 14 feet. Where the wall is from 10 to 12 feet, or higher, the Pear will suit better as a stock than the Quince, as it will grow quicker and fill up the space sooner. For a wall 12 feet high, 18 to 20 feet is a good distance to plant, while 20 to 24 will be better where the height is 15 or 16 feet. It is seldom that walls are much higher than this, but a good guide to planting is to put the trees one and a half times the distance from each other that the wall is in height.

When the trees deviate much either way from this rule, they do not look so proportionate or so well. Nothing looks worse than to see trees upon a 15-feet wall planted every 14 or 15 feet; or, what is even worse, to see a 9-feet wall with the trees planted 24 or 30 feet apart.

In concluding this chapter upon the Pear, it may not be out of place to make a few remarks upon walls. It is now a demonstrated fact, that of all materials used for garden walls, there is none so suitable, or which answers the purposes of fruit-culture so well, as brick. These, however, ought to be of the very best quality, as nothing can be more teasing than to see the bricks decaying from the effects of the weather, in the course of a few years after being built. The difference between good and inferior bricks is very trifling, while all the other materials and workmanship will be the same. The good old rule, therefore, holds good in this as in other cases - viz., get a good material, pay a good price for it, and you will get good satisfaction out of your bargain. The thickness of the wall will depend entirely upon the height thereof. A wall 9 inches in thickness - that is, one brick thick - should not be more than 6 or 7 feet high, as if higher they are sure to be soon affected by frost, rain, and wind to such an extent that their security is doubtful.

A wall from 6 to 12 feet should be 13 1/2 inches thick - that is, one and a half brick - which makes a very substantial wall, and at the same time does not require piers to strengthen it, which, at best, mar the beauty of the whole, while I am rather sceptical whether they met the end in view or not. All walls above 12 feet ought to be 18 inches in thickness, which will give them strength enough to resist the fiercest storms with impunity. Walls of this thickness may with benefit be made hollow, which does not in the least weaken them, while they are said to be warmer than those built solid. Various materials have been used for copings, but none answer the purpose so well as stone. Stone copings are more expensive at first, but the cheapest in the end, as all sorts of compositions are sure to crack in the course of time, and the rain entering through these cracks destroys the wall. Copings ought to rise in the middle and slope to the edge; and I would recommend that a gutter be cut along the edge 2 inches broad and one deep, which would prevent the drip from falling, as it often does in great quantities, upon the branches, foliage, and flowers of the trees, to their great injury and hurt.

If the coping is cemented together, the water could be led through these gutters to small lead pipes placed every hundred feet, which could empty themselves into the drains at the bottom of the walls.

About most places the south walls are all covered with either glass, Peaches, or Apricots. The next best situation must therefore be selected for the Pear. Most gardens are so placed as to face the sun from 10 to 11 a.m. In such a case the west side of the walls will be the best for the Pear, as it will not only be less exposed to the easterly winds and spring frosts, but will therefore have one hour more of the sun in this position than any other which could be assigned to it, unless the south; and many varieties of the Pear merit the latter position, which they do not often get. James M'Millan.