posed to the action of the sun have the most gay and glossy plumage, and it is probable that the metallic lustre and smooth surface of the plumage of tropical birds is a provision against the powerful heat and light, which is reflected as well as decomposed by that refraction which shows the colours. Bee-eaters are birds of warm, sunny climes, and of districts where sweet fruits are produced. They are not found in the New World, but appear to be represented in that continent by the genus Prionites. One species, Merops apiaster, or European Beeeater, has occasionally strayed into Britain. It is about eleven inches in length, the female being rather smaller than the male. The extent of the expanded wings is about seventeen or eighteen inches. The colour on the upper part is of a maroon red, fading into yellowish rust-colour on the middle of the back; the front of the head white, shaded with green; the eye-streak large and of a black colour; the quills and coverts olive-green; the neck golden yellow, marked in the middle with a half colour of black, and all the rest of the under part clear aqua-marine, or sea-green. The bill black and the feet brown. In the south-east and eastern portions of Europe, these birds are not uncommon during the summer. On the approach of autumn, they collect together in large flocks, and depart for more southern latitudes. It is so abundant in all the islands of the Archipelago and the Levant, as to be one of the most common summer birds. The climate of these islands is very fine, and as, from their comparatively small size, no part of them is at any great distance from water, they abound with insects, which afford subsistence to all the species of insectivorous birds, especially those which prey on the wing. . In these islands, the species under consideration is as plentiful and as familiar in its habits as Swallows are with us, only it builds, or rather burrows, in banks remote from human habitations. But, in search of its food, it flies in the close vicinity of houses; and in Crete especially, the boys are said to angle for it in rather a curious manner. They catch locusts, or any of the larger winged insects which have considerable power of flight, fasten the insect to a crooked pin or small fishhook at the end of a line, and letting the insect fly from the window, retain the line in their hand. The insect mounts up and endeavours to escape, notwithstanding the weight which it has to drag after it; and the Beeeater perceiving it in the air, snaps at it, is caught by the hook, and dragged home. This is perhaps one of the most singular modes of bird-catching, and yet anglers in this country sometimes catch Swallows involuntarily, in a manner nearly similar, by means of their artificial flies; and the writer has sometimes been astonished, in casting his fly, at throwing a Swallow on the water, instead of raising a trout.* The flight of the Bee-eater much resembles that of the Swallow, though it is more direct, and less rapid. The nest is formed in the sandy bank of some river, or sometimes in mountain ridges where the soil is loose. The depth of the excavation, according to Latham, is six feet. The eggs, which vary in num *British Cyclopædia. ber from four to six or seven, are white, and are deposited in a bed of moss, at the further extremity of the hole. It may be thought unnecessary to enter at any length into the habits and character of the Swallows (Hirundinida), so familiar are they to every one from their being so constantly on the wing, such confiding, friendly visitors to our houses, and so strikingly active in their motions; but their powers of flight are so extraordinary, and their mode of capturing insects so different to that of any other bird, that we cannot pass by the consideration of their structure and economy. These birds are observed during summer, from morning dawn till twilight closes upon the departing day, flying through the air with the greatest rapidity; skimming the surface of water, or gliding swiftly on motionless wing; turning and doubling, and darting like an arrow from a bow, with so much ease that but little exertion appears to be made by any of their limbs. It is evident, however, that they have to support themselves in the air as well as to make progress through it-that muscles must be in action; and it is surprising that they so seldom appear to need repose. They are for ever on the wing. The Swifts, which get their common name from the rapidity of their flight, are generally sixteen or eighteen hours on the wing every day, at that time of the year when they have their broods. During these hours it has been computed that they cannot, on the average, move over less space than a thousand or twelve hundred miles. The rapidity of their flight must require constant exertion, which cannot be kept up without a proportionate waste and a reparation of that waste, which is effected in some degree by means of respiration. The auxiliary breathing which they have in supplement to the common action of the lungs no doubt prevents the exhaustion of those organs, and checks fatigue, by the buoyancy which it gives to the bird. Feathers that take much hold on the air would impede their progress, and be the very worst adapted for them, and accordingly all their feathers are firm aud smooth; so that constant exertion is required to preserve their elevation in the air. The whole of the race are strictly insectivorous, and never destroy anything that is useful to man. How much they contribute to the preservation of many things that are valuable to him can scarcely be conceived, the number of insects that they capture being beyond computation. Many of the flies that are taken in the upper air by Swallows, are captured while winging their way for the purpose of depositing their eggs in situations where the grubs would be very injurious to vegetable life. Against these little depredators man has few direct defences within the range of his arts; and it is on this account that the insect-feeding birds, and the Swallows which obtain their food where no other birds can, are so very valuable, and are of such use in the economy of nature. But let us see how the Swallow is enabled to perform these feats, and what is the modification of form and power requisite for such a purpose. The general characters are readily perceived. They are all, observes a writer in the "British Cyclopædia," very thickly formed in the anterior part of their bodies, so that the whole mass is concentrated on the axis of the wings, and they taper off in beautiful curves toward the posterior extremity. Their wings are long and pointed, and remarkably compact in their texture, so that they can undergo a great deal of fatigue without injury; they are acuminated, which is the form best adapted for rapid and long-continued flight. The first quill is generally the longest, although it sometimes happens that there is scarcely a percep ་ $ tible difference between that and the second; the rest, however, gradually but regularly, diminish at almost equal intervals until they reach the lesser quills, which are little more than one-third the length of the exterior primaries, the whole of which are very broad, but gradually taper at their extremities. The lesser (secondary) quills, on the contrary, are not only unusually short, but terminate so abruptly that they appear to have their ends cut off at that part; however, there exists in the middle a distinct notch, or sinuosity, to break the passage of the air—a structure which is only carried to its maximum in the Bee-eaters. The tertials are very little longer than the secondaries, and hardly exceed the shortest of the primaries. It is thus obvious that the whole power of the wing is |