latter be much of a songster; but in this matter I want to be better informed. The former has a variety of hurrying notes, and sings all night. Some part of the song of the former, I suspect, is attributed to the latter. We have plenty of the soft-billed sort; which Mr. Pennant had entirely left out of his British Zoology, till I reminded him of his omission. See British Zoology last published, p. 16.* I have somewhat to advance on the different manners in which different birds fly and walk; but as this is a subject that I have not enough considered, and is of such a nature as not to be contained in a small space, I shall say nothing further about it at present.† No doubt the reason why the sex of birds in their first plumage is so difficult to be distinguished is, as you say, "because they "are not to pair and discharge their pa"rental functions till the ensuing Spring." As colours seem to be the chief external * See letter xxv. to Mr. Pennant. + See letter xlii. to Mr. Barrington. sexual distinction in many birds, these colours do not take place till sexual attachments begin to obtain. And the case is the same in quadrupeds; among whom, in their younger days, the sexes differ but little but, as they advance to maturity, horns and shaggy manes, beards and brawny necks, &c. &c., strongly discriminate the male from the female. We may instance still farther in our own species, where a beard and stronger features are usually characteristic of the male sex: but this sexual diversity does not take place in earlier life; for a beautiful youth shall be so like a beautiful girl that the difference shall not be discernible; "Quem si puellarum insereres choro, "Discrimen obscurum, solutis "Crinibus, ambiguoque vultu." HOR. LETTER VII. DEAR SIR; TO THE SAME. RINGMER, near LEWES, I AM glad to hear that Kuckalm is to furnish you with the birds of Jamaica; a sight of the hirundines of that hot and distant island would be a great entertainment to me. The Anni of Scopoli are now in my possession; and I have read the Annus Primus with satisfaction: for though some parts of this work are exceptionable, and he may advance some mistaken observations; yet the ornithology of so distant a country as Carniola is very curious. Men that undertake only one district are much more likely to advance natural knowledge than those that grasp at more than they can possibly be acquainted with: every kingdom, every province, should have its own monographer. The reason perhaps why he mentions nothing of Ray's Ornithology may be the extreme poverty and distance of his country, into which the works of our great naturalist may have never yet found their way. You have doubts, I know, whether this Ornithology is genuine, and really the work of Scopoli as to myself, I think I discover strong tokens of authenticity; the style corresponds with that of his Entomology; and his characters of his Ordines and Genera are many of them new, expressive, and masterly. He has ventured to alter some of the Linnaan genera with sufficient show of reason. It might perhaps be mere accident that you saw so many swifts and no swallows at Staines; because, in my long observation of those birds, I never could discover the least degree of rivalry or hostility between the species. Ray remarks that birds of the galline order, as cocks and hens, partridges, and pheasants, &c. are pulveratrices, such as dust themselves, using that method of cleansing their feathers, and ridding themselves of their vermin. As far as I can observe, many birds that dust themselves never wash: and I once thought that those birds that wash themselves would never dust; but here I find myself mistaken; for common housesparrows are great pulveratrices, being frequently seen grovelling and wallowing in dusty roads; and yet they are great washDoes not the skylark dust? ers. Query. Might not Mahomet and his followers take one method of purification from these pulveratrices? because I find from travellers of credit, that if a strict mussulman is journeying in a sandy desert where no water is to be found, at stated hours he strips off his clothes, and most scrupulously rubs his body over with sand or dust. A countryman told me he had found a young fern-owl in the nest of a small bird on the ground; and that it was fed by the little bird. I went to see this extraordinary phenomenon, and found that it was a young |