1 the gluten will prevent the sap that flows from the puncture, from being scattered or wasted; and the sap, being thus confined to the space occupied by the eggs, "will expand, and force outward the pellicle of gluten that confines it, till, becoming thickened by evaporation, and exposure to the air, it at length shuts up the puncture, stops the further escape of the sap, and the process is completed." But whatever the means may be, by which the effect is produced, it is perfect of its kind, and most admirably answers the end intended by the Almighty Contriver. In their most common form, the galls produced by means of these insects, may be found, in great numbers, during summer, on the leaves of the rose-tree, the oak, the poplar, the willow, and many other trees, in the globular form of a berry, about the size of a currant, and usually of a green color, tinged with red. When this pretty excrescence is cut into, it is found to be fresh, firm, juicy, and in the centre hollow, where there is either an egg or a grub safely lodged, and protected from all ordinary accidents. Within this hollow ball, the egg is hatched, and the grub feeds securely on its substance, till it prepares for its winter sleep, before changing into a gall-fly in the ensuing year. Most of the gall-flies deposit only one egg at a time, and, when that is the case, the gall generally assumes the form we have described; but the insect which makes use of the wild rose-tree, deposits several in one place, making, probably, as many punctures as she lays eggs. In this case, there is a much more abundant flow of sap from the wounds, and the effect is singular and admirable. The sap, instead of being evaporated or lost, shoots out into a reddish-colored fibrous bristle, about half an inch long, studded all over with a kind of pricklets, not unlike the moss on the flower-shoot of the moss rose. substance, within which the embryos of the future grubs are placed, is called bedaguar, by botanists. It swells to the size of a crab or small apple, and forms a bulb, having the appearance of a tuft of reddish-brown moss, stuck on or round a branch. Each member of the con This geries is found, on examination, to be furnished with its own tuft of bristles, arising from the little hollow globe in which the egg is lodged. "The prospective wisdom of this curious structure, is admirable. The bedaguar grubs live in their cells through the winter; and as their domicile is usually on one of the highest branches, it must be exposed to every severity of weather. But the close, non-conducting, warm, mossy collection of bristles with which it is surrounded, forms for the tender grubs, a snug protection against the winter's cold, till, through the influence of the warmth of the succeeding summer, they undergo their final change into the winged state; preparatory to which, they eat their way, with their sharp mandibles, through the walls of their little cells, which are now so hard, as to be cut with difficulty with a knife."* Another structure, similar in principle, but different in appearance, is very common upon oak trees, the termination of a branch being selected, as best suited for the purpose. The structure is rather larger than a filbert, and is composed of concentric leaves, diverging from the base, and expanding upwards, somewhat like an artichoke. Whether this leafy substance is caused by a superinduced disease, as the French naturalists think, or, more probably, by the tendency of the exuding sap of the oak to form leaves, has not been ascertained; but that it is intended, as in the case of the bedaguar, to afford an efficient protection against the weather to the enclosed eggs or grubs, there can be no doubt. That galls of various kinds, are formed by the puncture of different species of flies, is evident from what occurs upon the oak, on which are found two sorts of galls, of a structure quite different from that already described. One of these is the wellknown oak-apple, which is commonly as large as a walnut, rounded, but not quite spherical. The skin is smooth, and tinged with red and yellow, like a ripe apple. At the base, there is, in its earlier stage, a calyx or cup, of a few small brown *Insect Architecture, p. 377. scaly leaves, but these fall off as the season advances. If an oak-apple be cut transversely, there is brought into view a number of oval granules, each containing a grub, and imbedded in a fruit-looking fleshy substance, having fibres running through it; and, what is particularly remarkable, each of these fibres terminates in one of the granules, like a footstalk, or, rather, like a vessel carrying nourishment. The gall-insects are very various in their form and habits, some of them belonging to the tribe of aphides; and the galls they produce are not less diversified. These structures may be found on every part of a plant, whether branch, root, leaf, or bud. Nor are they confined to trees;-on thistles, on the ground ivy, and the germander, as well as on many other plants, they may be discovered. Some galls, found in foreign countries, are collected in great quantities for sale; and the gall-nut of a species of oak is particularly valuable, on account of its use as an ingredient in making common writing ink. There is something so very striking in the creative contrivances and adaptations observable in this mode of providing for the safety and future subsistence of the progeny of these insects, as to afford peculiar satisfaction and delight to an ingenuous mind inquiring into the existence and attributes of the Great First Cause. Let us take a summary view of the whole process. The problem is, what new means may be employed for affording a secure asylum, furnished with appropriate food, to the embryo of certain races of living beings. Vegetable nature possesses a property, by which the sap, when exuded under very particular circumstances, will form itself into a round hollow excrescence; and this is fixed upon for the intended object. The animals, whose offspring are to be thus reared, are furnished with eggs fitted to be hatched in such a situation, and to produce grubs whose food this very exudation shall afford. They are, at the same time, supplied with a most curious instrument, elaborately formed, and fitted in the most exact manner for making the particular puncture required in the plant se lected; and then they are endowed with an instinct which enables them to choose the precise plant, whether tree, shrub, or flower, to which the egg, the future grub, and the instrument, are all most curiously adapted; and to choose also the proper part of the plant, whether leaf, branch, stem, or root; and, still further, to deposit their eggs at the critical season, when circumstances all combine most favorably for the required flow of the sap, and for the production of the grub in such time as to be ready for its state of hybernation when winter arrives ;—all these, and various other circumstances, so evidently evince knowledge, contrivance, and forethought, as to form a combination of evidence in favor of an Intelligent Creator, at once amazing and irresistible. FIFTH WEEK-THURSDAY. REPRODUCTION OF INSECTS.-DEPOSITION OF EGGS IN THE BODIES OF ANIMALS, AND INSECTS' NESTS. BEFORE leaving the subject of the maternal instincts of insects, I must not omit to mention that the same kind of analogy is to be found here which pervades other departments of the animated world, that of one species of animals being reared or nourished at the expense of another. One or two examples of this provision, which, although somewhat startling on a first view, can yet be distinctly proved to be altogether consistent with that peculiar character of Divine wisdom and benevolence manifested in sublunary affairs, and productive of a preponderance of good, will be detailed in the present paper. Yesterday, some account was given of those very peculiar provisions, by which the vegetable kingdom is laid under contribution for the hatching and rearing of the grubs belonging to certain species of flies, by the formation of galls. Such of my readers as are familiar with the analogies of Nature, will not be surprised to discover, that, by a similar provision, the animal world is made to contribute to the same object. No person who has resided in a rural district during the warm weather of summer, can be ignorant of that sudden and uncontrollable impulse which so frequently seizes a herd of cattle, known by the appropriate name of startling,-when they run off across a field in full gallop, with their tails poked out behind them, and their necks stretched to the utmost length. Virgil, in his "Georgics,' gives a graphic description of this simultaneous fury of these naturally quiet and patient animals. The following is a nearly literal translation. Around the groves of Silarus, and glades Of green Alburnus, buzzing sharp and wild, But Estrus by the Greeks.-The madden'd herds, This terror does not appear to be occasioned by the pain of the inflicted wounds, for it is very doubtful if the ovipositor penetrates the skin, but rather by the wellknown buzz of the insect. Were it otherwise, the cattle would, in all probability, lash the fly off with their tails. Their instinctive fear prevents this, and causes them to run recklessly forward, as we have seen, with extended tail, while the little animal is securely performing its parental office. The startling may be the means intended by the Creator to prevent an over-production of the insect. Be this as it may, the egg, glued probably to the scared animal's hair or skin, is soon converted into a grub, being hatched by the natural heat and perspiration of the beast, and eats its way slowly under the skin, causing a lump as large as an acorn. The horse, the sheep, the rein-deer, and various other quadrupeds, are subject * Est lucos Silari circa ilicibusque, virentem Concussus, silvæque, et sicci ripa Tanagri.—Geor. iii. 146. |