Selborne, Aug. 17, 1768. I HAVE now, past dispute, made out three distinct species of the willow-wrens, (motacilla trochili,) which constantly and invariably use distinct notes. But, at the same time, I am obliged to confess that I know nothing of your willow-lark.* In my letter of April the 18th, I had told you peremptorily that I knew your willow-lark, but had not seen it then; but, when I came to procure it, it proved, in all respects, a very motacilla trochilus; only that it is a size larger than the two other, and the yellow-green

* Brit. Zool. edit. 1776, octavo, p. 381.

of the whole upper part of the body is more vivid, and the belly of a clearer white. I have specimens of the three sorts now lying before me; and can discern that there are three gradations of sizes, and that the least has black legs, and the other two flesh-coloured ones. The yellowest bird is considerably the largest, and has its quill-feathers and secondary-feathers tipped with white, which the others. have not. This last haunts only the tops of trees in high beechen woods, and makes a sibilous grasshopper-like noise, now and then, at short intervals, shivering a little with its wings when it sings; and is, I make no doubt now, the regulus non cristatus of Ray; which he says, "cantat voce stridulá locusta." Yet this great ornithologist never suspected that there were three species.*

* The three species of willow-wren spoken of in this letter, and which White has the merit of having first, in this country,

clearly distinguished, will be found described and figured in Yarrell's" British Birds," under the names of wood-warbler, willowwarbler, and chiffchaff. The first, which is the largest willowwren of White, the wood-wren of Montagu, and the sylvia sibilatrix of Bechstein, is distinguished at once from the other two by its longer wings, the broader streak of bright sulphur-yellow above the eyes, the brighter yellow-green of the upper parts, and the purer white underneath. The second, the middle willow-wren of White, the yellow wren of Montagu, and the sylvia trochilus of Latham, is distinguished from the former by its shorter wings and paler plumage, and from the chiff-chaff by its paler legs. This last, the least willow-wren of White, and the sylvia hippolais of some British authors, but not of continental, is characterised, as White observes, by its black (at least, dark) legs; but many specimens are very little smaller than the S. trochilus, and, in point of colours, the plumage scarcely exhibits any difference. The song of the three species is perfectly distinct in each, and is well described by White here, and in other of his letters.-L. J.

LETTER XX.

Selborne, Oct. 8, 1768.

It is, I find, in zoology as it is in botany; all nature is so full, that that district produces the greatest variety which is the most examined. Several birds, which are said to belong to the north only, are, it seems, often in the south. I have discovered this summer three species of birds with us, which writers mention as only to be seen in the northern counties. The first that was brought me (on the 14th of May) was the sandpiper, tringa hypoleucus; it was a cock bird, and haunted the banks of some ponds near the village; and, as it had a companion, doubtless intended to have bred near that water. Besides, the owner has told me since that, on recollection, he has seen some of the same birds round his ponds in former summers.

The next bird that I procured (on the 21st of May) was a male red-backed butcher-bird, lanius collurio. My neighbour, who shot it, says that it might easily have escaped his notice, had not the outcries and chattering of the white-throats and other small birds drawn his attention to the bush where it was; its craw was filled with the legs and wings of beetles.

The next rare birds (which were procured for me last week) were some ring-ousels, turdi torquati.

This week twelvemonths, a gentleman from London, being with us, was amusing himself with a gun, and found, he told us, on an old yew-hedge where there were berries, some birds like blackbirds, with rings of white round their necks: a neighbouring farmer also, at the same time, observed the same; but, as no specimens were procured, little notice was taken. I mentioned this circumstance to you in my letter of November the 4th, 1767: (you, however, paid but small regard to what I said, as I had not seen these birds myself:) but, last week, the aforesaid farmer, seeing a large flock, twenty or thirty,