end of a slip of card neatly brought up to the side of the insect as it stands on the setting-board. As the water evaporates, the wing will retain its form on the card, and this will drop off, when quite dry, by its own weight. Folded wings which have resisted all other remedies often yield to this.

The specimens, especially those of the larger insects, require a good deal of subsequent care. They are liable to turn greasy and soil the paper on which they are mounted; they are the prey of little mites as well as of larger insects; and if they are kept in the sun they are liable to fade. But wasps are plentiful, and we need not grudge a little trouble in setting a few specimens more or less, when it adds so much to the beauty of the cabinet to have each nest ornamented by its own wasps.

*

The knowledge of insects which is limited to the external appearances of dried specimens, is literally only superficial. We must take their outer case to pieces, and look inside it, and examine its disarticulated fragments, if we wish to study their natural history to any useful purpose. Insect anatomy is capital practice, but it is a study of much difficulty, requiring great patience; and, as we may calculate on spoiling many specimens, it is of importance to secure a supply of the largest wasps, and in the freshest and healthiest condition possible. The perfect females which are found in the spring seem to answer best. Having contracted with little boys to furnish these alive and unhurt in any required quan

* See Cuvier's opinion on this point, as told by Audouin, in ‘Kirby and Spence's Introduction to Entomology,' 7th edition, pp. 12, 13 note.

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tity, we should keep them in a broad-necked bottle till leisure and sunshine to examine them come together. A few strong straws, or light twigs, should be crumpled into the bottle for the wasps to cling to. They should have a little biscuit or sugar, and plenty of water; and be kept in the dark and cool till wanted.

The tools which we want are very few: no more than what each microscopist already has. With a sharp-pointed pair of scissors, a pair of dissecting forceps, two or three mounted needles, a leaded cork and a soap-dish full of water, our repertory is complete. Though the possessor of a binocular dissecting microscope may perhaps wonder how any one could not call this most useful instrument indispensable.

Fully believing that pain, as we feel it, is not an attribute of insects, I must yet own to a great horror of any signs of vitality whatever displaying themselves in a wasp under examination. So, before commencing the dissection, I like to feel quite satisfied that the insect is dead. All these dissections must be made under water, as the tissues are too soft to retain their figure without some such fluid support. It is easier to make the necessary openings in the integuments before fastening the specimen to the cork. Having done this, and pinned the insect out in such a way as to interfere as little with the dissection as possible, we have only to wait till the air-bubbles clear away to set to work. We may want the scissors occasionally, but the most useful instruments are the needles, always working under water.

Many structures of wasps have a peculiar conformation, and, of course, in wasps only can these be thoroughly investigated. Conversely, we should look in vain in wasps for much that we find in other insects. If our idea, however, of insect structure in general is to be drawn from one insect, a wasp will serve as well as any other example.

It might be said, fancifully perhaps, that in many respects an insect is like a vertebrate animal reversed. The student of human anatomy has his attention directed to each prominence on the outside of the bones as indicative of the strength of the muscle attached to it, and of the mechanical functions of the part. It is not outside, but inside the bones of insects that these indications are to be found, the same horny plates serving the purpose both of skin and bone. So again, while in Vertebrata the blood is brought from the tissues to the air in the lungs that it may be oxygenated, in insects, as we shall see, the air is brought to the tissues and to the blood lying loose in a series of membranous sinuses. And such illustrations might be multiplied.

Again, fancifully, it might be said, taking an illustration from the vegetable kingdom, that insects are endogenous, having their growth limited by their external investment, and their structure physiologically prescribing the term of their existence. Subject to such restrictions, and within these limits, nothing more beautiful or perfect in adaptation can be conceived than these tiny organisms. They illustrate perhaps the highest point to which organization can be carried on the endogenous plan. Larger size, capacity of growth, and longer duration of life, are

only attainable by a different arrangement of more varied materials.

The life of an insect has often served to point a moral as to our own present and future state, the grovelling worm-the pupa in its death-like sleep— and the perfect insect rising in all its new beauty from the grave, have been fancifully said to typify the successive stages through which our own being is destined to pass. But the illustration is neither as accurate nor as beautiful as that which St. Paul* adopts. For, though insects may be said to be perfect, as insects, each with their one idea, and for their one purpose, yet the imago should be called rather a changed than a perfected being. It has new faculties indeed, and a wider range, but it has often a less intimate relation with the world at large; and it often plays a less useful part in its winged form than it did as a grovelling worm. And in manymost insects-the shorter existence of the imago, compared with that of the larva, sadly mars the point of this illustration as a type of eternity.

The real analogies of insect life are to be read in quite a different way. Professor Owent has put this very happily:-"If the different stages in the development of man were not hidden in the dark recesses of the womb, but were manifested, as in insects, by premature birth and the enjoyment of active life, with a limitation of the developmental force to mere growth; if the progress of development was thus interrupted and completed at brief and remote periods, with great rapidity, and during

* 1 Cor. xv, 37.

+ Lectures on the Invertebrate Animals,' p. 248.

a partial suspension of active life; his metamorphoses would be scarcely less striking and extreme, as they are not less real, than those of the butterfly."

There are few insects which as obviously minister to our comfort and well-being as the honey-bees of which we take so much care, and which we regard affectionately as the type of useful industry. But, from the large quantity of rotten wood which they destroy, and of flies and caterpillars which they consume, we may fairly regard wasps as no less our real benefactors; and we may look with more forbearance on the toll which they exact from our gardens in the autumn in return. Among most insects, and perhaps cockchafers and blow-flies supply the most familiar instances, it is the larvæ themselves which prey directly upon the animal and vegetable matters intended for their food. But among wasps, and some other Hymenoptera, it is the perfect insect which collects the scattered materials, and thus occupies a much wider field than could come within the range of the larva. These materials are rotten wood and garbage of all kinds, and, besides these, all the insects that they can master. It will be admitted that they devote themselves to this part of their duties with great assiduity, making prize of all flies, spiders, and caterpillars; bees, and even other wasps, not being excepted. It would be very difficult to prove absolutely that wasps have a sensible influence in diminishing the number of flies and of other insects. But it is the conviction of some of those who have paid attention to the subject that this is really the case. Among others, Mr. A. Bryson, F.R.S.E., of Edinburgh, the friend and