CHELIDOSIAN BIRDS.
Bill very short, much depressed, and very wide at the base ; the upper mandible curved at the point ; legs short; three toes before, either entirely divided, or connected at the base by a short membrane, the hinder often reversible, the claws much hooked ; wings long. The flight of these birds is rapid and abrupt, their sight piercing, neck short, throat wide, bill broad, and often gaping for the reception of insects, which constitute their only food.
IiinuNno, Lin. Sec. SWALLOW.
Bill short, triangular, broad at the base, depressed, cleft near to the eyes ; upper inaudible slightly hooked at the, tip ; nostrils basal, oblong, partly closed by a membrane, and surmounted by feathers in front ; legs short, with slen der toes and claws ; wings long, the first quill the longest; tail mostly forked.
The swallow tribes manifest a predilection to the neigh bourhood of water, and those situations in which insects most abound. These last they seize with great "iron pti tude in their long sustained and very rapid flights. They catch their food, drink, and bathe, as they glide smoothly and nimbly along the surface of the water. Their motions are easy, swift and graceful ; and, when not occupied with breeding or sleep, they are almost incessantly on the wing. Their nests, when dried, arc hard and rough on the outside, but furnished with soft materials within. 'While they rid our orchards, gardens and houses, of legions of insects, they never attack the produce of the soil. Their lively manners, twittering note, and gentle and affectionate dispositions, amply repay the shelter which our buildings afford to several of the species. Their mi grations are no longer matter of doubt ; and the observa tions of Natterer of Vienna have established the important fact, that they moult in February, which is a fresh argument against their alleged torpor in winter. All the species are more or less infested by the Hiplzobosca hirundinis, which abounds in their nests, is hatched by the warmth of the bird's own body during incubation, and crawls about under its feathers.
I!. rustica, Lin. Scc. Common Chimney, or House Swallow. Black-blue above, whitish beneath ; forehead and throat of a reddish aurora tint ; and all the tail feathers but the two in the middle marked with a white spot. The tail is much forked, the legs are dusky, and the lateral quill feather on each side is an inch longer than the inter mediate ones. Length of the body six inches and a half, alar extent nearly one foot, and weight between five and six drachms. The colours of the male are more lively than those of the female, and the exterior feathers of his tail are somewhat longer ; the colouring of the young also is much less lively than that of the adults. An entirely white variety sometimes occurs. Some have been found of a yellowish-white, with the other colours faintly im pressed on some parts of the body, and others more or less speckled with white.
This well known species occurs almost every where in the old continent. It visits us earlier in the season than any of its congeners ; usually, if the weather be mild, about the beginning of April, or a week before the house martin, and it retires about the end of September, or beginning of October. In this country it usually builds in the inside of our chimneys, at a few feet from the top ; but it will also affix its nest to the beams and rafters of outhouses; and in some countries, it not unfrequently constructs it against rocks, or even in trees. At Camerton llall, near Bath, a pair built their nest on the upper part of the frame of an old picture over the mantle-piece, entering through a broken. pane in the window of the room. Hither they resorted three years successively, when their access was precluded by the room being put in repair. But what is still more eccentric, a bird of the same species built its nest on thz wings and body of an owl, which happened by accident to hang dead and dry from the rafter of a barn, and so loose as to be moved by every gust of wind. The carcass, with the nest on the wings, and with eggs in the nest, was brought as a curiosity to Sir Ashton Lever, who, struck with the oddity of the sight, furnished tile person who brought it with a large conch-shell, desiring him to fix it just where the owl had been suspended. This was dune accordingly, and the following year a pair of these birds, probably the same, built their nest in the shell, and the fe male laid eggs as usual. The owl, and its comiterpart the shell, made a singular and grotesque appearenee in the Leverian collection. Wonderful is the address which this bird exhibits in ascending and descending with security through the narrow passage of a chimney. When hover ing over the mouth of the funnel, the vibration of its wings, acting on the confined air, occasions a rumbling like dis tant thunder. It is not improbable that the dam submits
to the inconvenience of having her nest low down in the shaft, in order to secure her brood from rapacious birds, and particularly from owls, which arc frequently found to fall down chimneys, probably in their attempts to get at the nestlings. The experiments of Frisch and others prove, that chimney swallows annually return to the same haunts ; but they generally build a fresh nest every season ; and, if circumstances permit, they fix it above that ‘v hich was occupied the preceding year. Montbeillard has found them in the shaft of a chimney thus ranged in tiers, four of the same size, one above another, composed of mud ranced with straw and hair. They were of the largest size, resem bling a hollow half cylinder% open above, a foot in height, and attached to the sides of tne chimne) , hile some of small er dimensions, and forming only the quarter of a cylinder, or even an inverted cone, were stuck in the corners. The first nest, which was the lowest, had the same texture at the bottom as at the sides ; but the two upper tiers were separated from the lower by then• lining only, which consisted of straw, dry herbs, and feathers. Of me small nests in the corners of the chimneys he could find only two in tiers ; and he supposed that they belonged to young pairs, for they were not so well compacted as the large ones. The eggs of the first brood are four or five, white, and speckled with rusty red, and those of the second con sist usually of two or three. While the female sits, the male, who sings the amorous ditty, passes the night on the brim of the nest, but sleeps little ; for his twittering is heard with the earliest dawn, and he circles about almost till the close of evening. After the young are hatched, both parents perpetually carry food, and are at great pains to ktep the nest clean, till the brood have learned to save them that trouble. Boerhaave relates, that a swallow, returning with provisions to its nest, and finding the house on fire, rushed through the flames to feed and protect her offspring. It is pleasing to see the parents employed in teaching their family to fly, encouraging them with their voice, presenting food at a little distance, and retir ing as the young ones stretch forward, pressing them gently from the nest, fluttering before them, and offering, in the most expressive tone, to receive and assist them. The young, not without difficulty, first. emerge from the shaft; for a day or two they are fed on the chimney top; and they are then conducted to the dead leafless bough of some neighbouring tree, where, sitting in a row, they are attend ed by the parents with great assiduity. In a day or two after this they arc strong enough to fly, but continue still unable to take their own food : they, therefore, play about near the place where the dam is watching for flies, and when a mouthful is collected, the darn and the nestling, on a given signal, mutually advance, rising towards one ano ther, and meeting at an angle, the young all the while ut tering a short quick noteof gratitude and complacency. As -soon as the female has disengaged herself from the first brood, she immediately commences her preparations for a second, which is hatched about the middle or latter end of August. During every pari of the summer, in short, she is a pattern of unwearied industry and ;Affection; for, while there is a family to support, she skims along from morning to night, or exerts the most sudden turns. 91' quick evolutions, preferably frequenting avenues, long walks under hedges, pasture fields, and mown mea dows, in which cattle graze, because in such situations insects most abound. On downs, these birds may be seen to follow, and with great ease to fly repeatedly round a horse that is travelling at a smart trot, in order to pick up the flies roused from the turf by the motion of the ani mal's feet. When a fly is taken, a person may hear a snap of the bill, not unlike the noise of shutting a watch case; but the motion of the mandibles is too quick for the eye. As the winged insects fly higher or lower, according to the greater or less degree of heat, the swallows, in pursuit of their prey, sometimes skim along the surface of the ground, and sometimes take a more elevated flight, and, when a scarcity of insects prevails, they snatch flies from spiders webs, and even devour the spiders them selves. About the close of summer, they not unfrequently pass the night perched on alders that grow on the banks of brooks and rivers ; and, at that season, numbers rf them are caught in some countries for the table.