ICHNEUMONS OF ALL SIZES.

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Even with a group of insect eggs, guard them as we may, we can never be certain that some parasitic occupant has not possessed them before ourselves. Kirby tells us of ichneumons so minute as to occupy, between two, one egg of a butterfly; and Bonnet speaks of the same confined receptacle as affording board and lodging to several of these tiny interlopers. When told that out of sixty eggs of the emperor moth, not one was found exempt from their intrusion, we may imagine the large proportion of caterpillars nipped in the embryo, as well as in their growth, by parasitic enemies. Amongst these, all are subject to attack by similar destroyers of various size proportioned to the bulk of their victims, from the minute grub of the leaf-miner, to the bulky caterpillar of a puss-moth or a sphinx; and commensurate with this wide extent of damage to the caterpillar crew, is, of course, the benefit to the vegetable world and the human race, through these parasitic agents, which, while emblems of evil, are thus made instruments of good.

Though the gay and beautiful order Lepidoptera thus holds a dangerous pre-eminence as an object of parasitic attack, it is not alone the butterfly and moth which are often robbed by the same agency of their last estate and brightest inheritance.

We have seen already how a common ichneumon, with a tail-like ovipositor of prodigious length, is accustomed to assail, in the deep nest-hole of a mason wasp, the infant progeny of an insect of its own order, that of Hymenoptera; and

we shall briefly notice, now, the invasion of an infant asylum of somewhat similar construction, wherein, however, a parasitic wasp is the aggressor, and a solitary carpenter bee the maternal guardian, whose cares are often rendered nugatory by its cunning.

The waspish lady (in this case the agressor) is, however, we can tell you, Reader, a wasp of no common order; but one which, for beauty and splendour, has never met her match in the waspish world, nor her superior, perhaps, in the whole world of British insects. You must surely have sometimes seen her, a perfect living jewel as she is! with head, breast, and shoulders all thickly set with emeralds, outshone only by the ruby-red and burnished gold which mingle in her fiery tail. You must have seen, and certainly have noted, such a notable as this, when alighted, according to her wont, in the hottest summer sunshine, upon posts and railings; but you may not know her by the names either of "Chrysis," of "Golden Wasp," or of "Ruby-tail Fly;" or even if you know her names, you may not be acquainted with her business-her business, that is, upon posts and railings. Never suppose that she so often visits these uninviting, flowerless, dry localities, merely to bask in the sultry sunbeams, or challenge them to outshine her golden splendour. No; this creature, in her glorious array, is bent on glorious mischief. You may, one day, happen to perceive, on the same post as that chosen for her station by the golden wasp, a hole bored in the wood, and

you may also possibly see its borer, in the shape of a little bee mother, of the carpenter craft, who with infinite pains and labour has chiselled out with her jaws a nursery tunnel, divided it into cells, and stored it with provision for her young. But, ah! that bejewelled ruby-tailed pryer has also watched her in her tender labours, which she will take good care to convert, if possible, to the benefit of her own waspish offspring. Only behold her (like a fiend in angel's guise) lurking to effect her purpose. She has deserted her sunny post, and hides her glittering form under the covert of some neighbouring leaves, her glowing eyes fixed, though, all the while, upon the nest of her humble cousin Bee. She has seen her return, her thighs laden with the golden pollen which she has been collecting for her nestlings' store; but still, it wants completion, and she (poor busy mother!), meaning shortly to return, repairs once more to a neighbouring garden, to load herself again with sweet provision. But no sooner does she issue from her nest-hole, than the wily parasite darts from behind her screen, her dazzling body and glittering wings flash for a moment in the sun, then suddenly are lost in the dark perforation of the tunnelled bee's nest. Woe then to its hapless tenants! They may feast awhile upon the sweets provided by maternal care; but they will feast and fatten only to be devoured by a grub of the golden wasp, who, in her visit to their nest (fatal as it is brief), has deposited an egg, or eggs, from whence will issue all this murderous mischief.

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PREY OF PARASITES.

While the infant bee, deep in its perforated cell, is exposed to dangers such as these, the embryo gall-fly sleeps not a whit more safely within its pulpy or woody globe, pierced, often, to the centre, by the egg-inserting instrument of a gall ichneumon. Even the little aphis, or plant-louse, cannot escape, through its minuteness, from the punctures of an ichneumon parasite proportioned to itself; and the aphides' archenemy, the ladybird, while yet an aphis-eating larva, is preyed upon in turn by a parasitic consumer.

The student of insect economy will meet continually with resembling instances of parasitic usurpation, at which, till acquainted with its true character, he may often be disposed to wonder almost as much as the early naturalists. Some of these, not a little puzzled by such strange procedures as that of an ichneumon from the egg of a butterfly, or from the nut or apple of a gall-fly, attributed the mystery, for which they wanted a key, to the occasional insufficiency of Dame Nature's producing power, causing her, at times, when she had planned a magnificent butterfly, to turn out only a vulgar fly.

All the parasites above noticed, if not ichneumons, are, be it remembered, flies-parasitic flies,-either four-winged, of the order Hymenoptera, or two-winged, of the order Diptera. They are all, also, when arrived as perfect insects at their winged estate, livers upon vegetable food,—for themselves, usually, mere harmless sippers of honey. Only in the parental character are their cruel and parasitic propensities developed, to be

PARASITES ON PERFECT INSECTS.

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exercised either on living subjects, affording at once a cover for their eggs and nourishment for their young, or else upon those stranger nests wherein is to be found both shelter and a store of living prey suitable for the same purposes. The sufferers in these cases are all also immature, being still either in the first or second stage of existence.

But there are certain other insect parasites (chiefly wingless, and of the order Aptera) which are parasitic entirely for themselves, perfect insects which infest others, perfect also. Of such are the Acari, or mites, with which all, who have ever noticed the commonest of black beetles, must have sometimes seen them covered, as well as their pretty cousins the gold green chafers of the rose. The humble bee is another not unfrequent sufferer from somewhat similar infestation, which is said, moreover, to rob, occasionally, the merry grasshopper of his juices, if not of his enjoyment. These, however, with other parasitic tormentors whose visitations extend to bird, and beast, and man, may be looked on more properly as a part of the vermin crew, not now the subject of our notice.

Enough, too, of insect preying upon insect. But before we have done with parasites altogether, we must say a concluding word or two of insects as now and then preyed upon by plants. We are told by physiological botanists, that plants with few and small leaves depend chiefly for their food upon the soil; those with many and large ones, more upon the atmosphere; and in the Chinese air-plant we have the phenome