city in a willow-wren, which had built in a bank in my fields. This bird a friend and myself had observed as she sat in her nest, but were particularly careful not to disturb her, though we saw she eyed us with some degree of jealousy. Some days after, as we passed that way, we were desirous of remarking how this brood went on; but no nest could be found till I happened to take up a large bundle of long green moss, as it were carelessly thrown over the nest, in order to dodge the eye of any im. pertinent intruder.

A still more remarkable mixture of sagacity and instinct occurred to me one day, as my people were pulling off the lining of a hotbed in order to add some fresh dung. From out of the side of this bed leaped an animal with great agility, that made a most grotesque figure; nor was it without great difficulty that it could be taken, when it proved to be a large white-bellied field-mouse, with three or four young clinging to her by their mouths and feet. It was amazing that the desultory and rapid motions of this dam should not oblige her litter to quit their hold, especially when it appeared that they were so young as to be both naked and blind!

LETTER XV.

Selborne, July 8, 1773. DEAR SIR, SOME young men went down lately to a pond on the verge of Wolmer Forest to hunt flappers, or young wild ducks, many of which they caught, and, among the rest, some very minute yet

well-fledged wild-fowls alive, which upon examination I found to be TEALS. I did not know till then

that teals ever built in the south of England, and was much pleased with the discovery: this I look upon as a great stroke in natural history.

We have had, ever since I can remember, a pair of white owls that constantly place their nest under the eaves of this church. As I have paid good attention to the manner of life of these birds during the summer through, the following remarks may not, perhaps, be unacceptable. About an hour be fore sunset (for then the mice begin to run) they sally forth in quest of prey, and hunt all round the hedges of meadows and small enclosures for them, which seem to be their only food. In this irregular country we can stand on an eminence and see them beat the fields over like a setting-dog, and often drop down in the grass or corn. I have minuted these birds with my watch for an hour together, and have found that they return to their nest, the one or the other of them, about once in five minutes; reflecting, at the same time, on the adroitness that

every amimal is possessed of as far as regards the well-being of itself and offspring. But a piece of address which they show when they return load. ed, should not, I think, be passed over in silence. As they take their prey with their claws, so they carry it in their claws to their nest; but, as the feet are necessary in their ascent under the tiles, they constantly perch first on the roof of the chancel, and shift the mouse from their claws to their bill, that the feet may be at liberty to take hold of the plate on the wall as they are rising under the

eaves.

WHITE OWLS seem not (but in this I am not pos

itive) to hoot at all; all that clamorous hooting appears to me to come from the wood kinds. The white owl does indeed snore and hiss in a tremen. dous manner; and these menaces will answer the intention of intimidating, for I have known a whole village up in arms on such an occasion. White owls also often scream horribly as they fly along; from this screaming probably arose the common

people's imaginary species of screech-owl, which they superstitiously think attends the windows of dying persons. The plumage of the remiges of the wings of every species of owl that I have yet examined is remarkably soft and pliant. Perhaps it may be necessary that the wings of these birds should not make much resistance or rushing, that they may be enabled to steal through the air unheard upon a nimble and watchful quarry.

While I am talking of owls, it may not be improper to mention what I was told by a gentleman of the county of Wilts: As they were grubbing a vast hollow pollard ash that had been the mansion of owls for centuries, he discovered at the bottom a mass of matter that at first he could not account for. After some examination, he found that it was a congeries of the bones of mice (and perhaps of birds and bats), that had been heaping together for ages, being cast up in pellets out of the crops of many generations of inhabitants. For owls cast up the bones, fur, and feathers of what they devour, after the manner of hawks. He believes, he told me, that there were bushels of this kind of substance.

When brown owls hoot, their throats swell as big as a hen's egg. I have known an owl of this species live a full year without any water. Perhaps the case may be the same with all birds of prey. When owls fly, they stretch out their legs behind them as a balance to their large heavy heads; for, as most nocturnal birds have large eyes and ears, they must have large heads to contain them. Large eyes, I presume, are necessary to collect every ray of light, and large concave

ears to command the smallest degree of sound or noise.

It will be proper to premise here, that the sixteenth, eighteenth, twentieth, and twenty-first letters have been published already in the Philosophical Transactions; but, as nicer observation has furnished several corrections and additions, it is hoped that the republication of them will not give offence, especially as these sheets would be very imperfect without them, and as they will be new to many readers who had no opportunity of seeing them when they made their first appearance.

The hirundines are a most inoffensive, harmless, entertaining, social, and useful tribe of birds; they touch no fruit in our gardens; delight, all except one species, in attaching themselves to our houses; amuse us with their migrations, songs, and marvellous agility; and clear our outlets from the annoyances of gnats and other troublesome insects. Some districts in the South Seas, near Guyaquil,* are desolated, it seems, by the infinite swarms of venomous moschetoes which fill the air, and render those coasts insupportable. It would be worth inquiring whether any species of hirundines is found in those regions. Whoever contemplates the myr. iads of insects that sport in the sunbeams of a summer evening in this country, will soon be convinced to what degree our atmosphere would be choked with them was it not for the friendly interposition of the swallow tribe.

Many species of birds have their peculiar lice; but the hirundines alone seem to be annoyed with dipterous insects, which infest every species, and are so large, in proportion to themselves, that they

* See Ulloa's Travels.