H. rustica, or the house-swallow, ap pears in March, in England, and leaves it in September. It generally builds in chimneys, or under the eaves of houses, and will return, unless interrupted, to its original haunt for a number of years. For three years in succession apair of swal lows built on the frame of an old picture in Camerton Hall, near Bath, having ac cess to the apartment through a broken pane in the window. These birds breed twice a year. They are easily rendeied familiar; and it has been calculated, from what occurred in a curious and extraordi nary instance of the domestication of of them, in the family of a gentleman in Northumberland, that a single swallow will devour from seven hundred to a thousand flies in one day. See Ayes, Plate VIII.
H. urbica, or the martin, arrives in Eng land rather later than the swallow, and re mains longer. It builds often in the crags of rocks, near the sea ; often under the eaves and cornices of houses. As soon as the young are able to fly, they are fed by the old birds upon the wing, by a process so rapid and instantaneous, as almost to be deemed incredible by those who have not actually witnessed it. Before their depar ture they collect in immense flocks in the small islands of the Thames, where they roost, and in their flights about which they almost obscure by their num bers the face of the sky. It is observed, that in comparison with the multitudes which depart, there are extremely few which return. See Ayes, Plate VIII. fig. 3.
H. apus, or the swift, arrives in Eng land later, and quits sooner, than any other species,and is also larger and strong er. It builds in elevated situations, parti cularly about churches and steeples. As • these birds catch at almost every thing in the air, they are taken sometimes by a cockchafer, or other insects tied to a thread. In the Isle of Zante this torturing amusement is practised on them by boys, who catch them indeed often in immense numbers by a string and feathered hook only, which they suspend from some ele vated situation. They retire during the
heat of the day ; but in the morning and evening are incessantly on the wing, tak ing higher and bolder flights than the swallows, and always keeping separate from them. They leave that island in August. See Ayes, Plate VIII. fig. 4.
H. esculenta, or the Chinese swallow, is said to be less than the wren by some authors, while others attribute to it the size of the martin. This bird is principal ly remarkable for its nest, which, singu lar as it may appear, is not only used for food, but regarded as one of the greatest luxuries on which the genuine epicure son possibly banquet: The weight of this nest is about half an ounce : it is formed in the shape of a half of a lemon, and composed of many easily discriminated layers of a substance somewhat resem bling isinglass. The materials which con stitute it have been the subject of consi derable diversity of opinion, and are not vet (at least in this country) ascertained. it is chiefly applied in soups and ragouts, made of chickens, and mixed with a con siderable quantity of ginseng.
Mr. Wilson describes a new species, inhabiting the United States, under the name of viridis, or green-white bellied : it is greenish above, with the wings and tail brownish-black, all be neath pure white. Besides this there are four other species.
H. Americana,. rufus-rumped, or barn swallow, of which the rump and vent feathers are rufous H. purpurea, entirely violet, tail-fork ed, attacks and drives from its haunts lar ger birds.
H. riparia, bank, or sand swallow, cine reous, chin and belly white : builds in holes in gravel pits and banks of rivers.
H. pelasgia, aculeated, or chimney swallow, tail feathers of equal length, na ked and subulated at the end.