ing ominously, of their notions, such an idea as

Now, absurd as are many gained so universal a hold without having this could not have it, which element I take to be this. some element of truth in form the food of very many insects. The arise The Aphides upon them, and so do those of of the Ladybirds feed entirely both of which insects have already been the Lacewing-flies, eaten by the larvse of the swift and

described. They are also

active Sjrpbida, which will presently be mentioned. Several Hymen optera provision their nests with them, and others of the parasitic kind, such as Chalcidicse, Proctotrupidse, Cynipidse, and Ichneumonidas.

As to these last insects, the mode in which they operate on tlie Aphis is very remarkable. As may be inferred from the size of the Aphides, on which they are parasitic, they are of very small dimensions, and one of these tiny creatures when standing on the back of an Aphis which it is about to wound, looks much like a rook perched on a sheep’s back.

When the fatal egg has been introduced under the skin of the Aphis, the wounded insect, like the stricken hart, separates itself from its fellows and passes to the under side of a leaf, and there fixes itself. Its body soon begins to swell, and at last becomes quite globular and horny, the change being caused by the death of the Aphis and the rapid growth of the parasite within it. The ichneumon passes rapidly through its changes, and in a short time assumes the perfect form, always with its head next the tail of its victim, pushes off the last two or three segments of the dead Aphis and makes its escape into the world. The dead and empty skins of such hapless Aphides may be found plentifully towards the end of summer, sticking firmly to the leaf, and showing the round aperture through which the destroying parasite has crept.

Sometimes there is a sort of contest between the Aphis and the ichneumon-fly, the former, however, having no more chance against its tiny foe than has a rabbit against a weasel. If the Aphis have its beak deeply plunged into the bark, the ichneumon-fly has an easy task, for the Aphis can do nothing but kick and struggle while anchored to the spot by its proboscis, and all that the ichneumon-fly has to do is to make its deadly lunge. But, if the Aphis be wandering about the plant, the ichneumon-fly has to walk about with it, and try first one side and then the other, until she can find an opportunity of depositing her egg.

We now come to a very remarkable group of Aphides which have been gathered together under the generic name of Eriosoma, or Wool-bodied, because their bodies are covered with a substance like very fine cotton wool. These insects N N 2

do not possess the honey-dew distilling apparatus, and the antennae are shorter than in the generality of the Aphidae. Tlie peculiarity, however, which principally distinguishes them is the envelopment with woolly fibre, which almost entirely covers the body, and renders it so light in comparison with its size that it can be blown through the air like a small tuft of swan’s down, and in this way it passes from one locality to another. The best known of these insects is that which is poprdarly called American Blight {Eviosoma aphis, or Lachnus lanigera), which sometimes overruns our orchards in a marvellously rapid manner, and sometimes destroys hundreds of apple-trees by its vast numbers.

The following graphic and amusing description of this insect, and the best mode of getting rid of it, is gTven in the ‘ Letters of Eusticus,’ to which reference has already been made : —

‘ I don’t know why our brethren on the other side the Atlantic are charged with sending us the gTeatest pests of oiur orchards, but so it is. We call an insect the American Blight, which, for aught I could ever make out, may have come from China or Botany Bay. However, a name once in vogue will have its day ; and one might as well attempt to turn a pig in an entry as argue against an established belief, so American Blight it shall be. In very hot weather you may now and then see this Blight on the wing ; it has just the look of a bit of cotton, or a downy seed, floating in the air, and is driven by every breath of wind quite as readily.

‘ If you catch and examine it, you will find it to be just like the plant-louse which infests our rose-trees, &c. ; but, vmlike all other plant-lice, it is clothed and muffled up with cottonwool in such quantities, that you would at first have no more idea that the lump contained an insect than that the mass of clothes on a stage-coach box in winter contained a man. Some folks wonder what can be the use of so much clotliing ; I am not much of a theorist, but I should guess that the vermin came from the torrid zone, and nature kindly furnishes this garment to protect them from the cold of our climate.

‘ These Blights wander wherever the wind pleases to carry them ; and if bad luck should drive one of them against the branch of an apple-tree, there it will stick, creep into a crack bark, bring forth its young, and found a colony. I he in the

white cotton soon appears in large bunches ; branch after, branch becomes infected ; the tree grows cankery, pines, and dies. How this is effected no one knows, though the plague and its doings are too evident to escape the notice of the commonest clown.

‘ In large orchards it is in vain to hope for a cure, but not so in gardens. ' Directly you see the least morsel of cotton, make up your minds to a little trouble, and you will get rid of it. In the first place, get a plasterer’s whitewashing brush, then get a large pot of double size, make your man heat it till it is cpiite a liquid, then go with him into the garden and see that he paints over every patch of white, though not bigger than a sixpence ; the next morning have the size-pot heated again, and have another hunt, and keep on doing so every morning for a fortnight. Your man will tell you it’s no use ; tell him that’s your business, not his : your neighbours will laugh at you for your pains ; do it before they are up. I have tried it and known it to be effectual. Spirit of tar has been used with partial effect, so also has resin ; whitewashing has been often tried, and, as it contains some size, is not entirely useless, and some horticultiu'ists think it ornamental ; I do not.’

Even in the winter time the task of extermination can be carried on. When the weather becomes cold, the Aphides crawl down the trunks of the trees and hide themselves among the roots below the surface of the soil. As they cannot endure the cold, the best way of getting rid of them is to expose them to it. So, in the depth of winter, when the thermometer is at its lowest, an inch or two of soil should be scratched up around the trunks of the trees, so as to expose the roots and let the cold air upon the Aphides that are in hiding. The ground should be freshly turned up every day while the frost lasts, and, when the thaw comes, the ground should be well saturated with a solution of ammonia before the earth is replaced. The ammonia-water from the gas-works is amply sufficient for this purpose, is very cheap and easily obtained.

We now come to the last great group of the Homoptera, namely, the Monomera, or those which have but one joint in the tarsus. These are all included in the genus Coccus, popularly known as Scale Insects, on account of the singular form

of the female, and Mealy-Bugs, on account of the white substance which envelopes the young Cocci. Mr. Westwood remarks that these form ‘ one of the most anomalous tribes of insects with which we are acquainted, and which already prove that annulose animals may exist, which become more and more -imperfect as they approach the winged state, and which in that state lose all trace of articulation in the body as well as of articulated limbs (as in the female Cocci), leaving, in fact, inert and fixed masses of animal matter, motionless and apparently senseless, and which resemble nothing more nearly than the vegetable excrescences called galls.’ The same eminent entomologist also points out the remarkable analogy which exists between the Coccidse among the insects, and the Cirrhipeda, or Barnacles, among the Crustacea.

It is rather difficult to find a starting-point for the history of this remarkable insect, but we will begin at the early larval condition. In this state both sexes are alike, very small, and nearly as large as the dot over the letter i ; six-footed, active, and having two long and slender bristles at the end of the body. When they are large enough to shift for themselves, they proceed along the branches and fix their beaks into the bark of the twig, or the spider-veins of the leaf, and remain from that time motionless, growing rapidly in size, but losing the tail-bristles. Thus they remain throughout the winter, and not until the following spring do the sexes develope themselves ; the males assuming their wings and taking to flight, and the females remaining where they were. The subsequent career of the insect has been traced by Alphonse Karr, in his ‘Voyage autour de mon Jardin,’ a translation of which was by Messrs. Eoutledge and Co. in 1854 : — published journey once completed, it will repose after it for the

‘ The rest of its life. It will fasten itself to a young branch, and not only will it never leave it again, but, still further, it will never quit the point of the branch upon which it has established itself. It grows — that is its mission, that is its duty. When it become as large as a pea, there comes a most singular little red, with two wings twice as long as its body. fly, of a deep These wings are of an opaque white, ornamented on the outward side by a rich carmine band. These little flies are the males of the animated tubercles.

‘ Among these insects may be seen that which the Komaus required of woman carried to the highest degree — Liinam fecit, domutn servavit. She spun her wool and kept her house. While the male — small, rakish, nobly clothed in purple — flies about at hazard, the female, scarcely living, taken for^ a gall of the tree, for the swelling of a leaf or brancli, remains motionless and waits for her husband. The male, who is small in comparison, walks over her, surVeys her singularly all over, for she is for him a sufficiently large tract. He examines her from north to south and from east to west, and it is not until he is fatigued with running about over his beloved object that he risks the avowal of his flame ; after which, flying once or twice round his beloved, he departs.

‘The wife from that moment thinks of nothing but the numerous family she has to bring into the world— about two thousand children. She begins to lay, and her eggs all come enveloped in a sort of cotton. LqiTI/Cltyi

‘ Then the Scale Insect changes its form — its belly flattens and becomes so thin that it joins the back ; which forms a hollow space under it in which are its eggs. Its back hardens, the belly and the back are quite confounded ; the Scale Insect withers, dies, and becomes a dwelling-place for its young ones. This is better than the domum servavit ; she does not remain in the house, she becomes the house itself.’

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