of some species of birds even within a very limited area. An immense number of Missel-Thrushes' nests have come under our observation, but never one, in this district, has been built in any other situation than either in trees or bushes, very seldom comparatively in the latter. On the other hand, this species breeds not uncommonly in walls on the moors a little to the north of Bolton Woods, in Wharfedale, which are also well wooded—chiefly pine and larch with little or no underwood—and only some twenty miles in a bee-line north of this place. Both the Song- and Missel-Thrush are met with in much more varying numbers during the breeding season than the Blackbird, and in winter—even the severest winters—a much greater number of the latter remain compared with the number which obtains during the breeding season.—E.P. Butterfield (Wilsden, near Bradford).
Abnormal Nesting Sites of the Willow-Wren.—With reference to Dr. A.G. Butler's note on highly-placed nests of the Chiffchaff, I may mention that I have frequently found them situated as much as four feet from the ground, but never higher; a pair built for several years in succession in the top of a box-tree, a little over four feet, in the garden of a friend of mine. During the last spring and summer I have seen three nests of the Willow-Wren (Phylloscopus trochilus) in situations which, in the case of two of them, are unique in my experience. One was placed five feet from the ground in a spruce-fir, surrounded by a wild rose bush, built on a flat bough of the spruce, and entwined in the twigs of the rose. Of the other two, which were within a mile of each other, one was placed in an old Marsh-Titmouse's nesting-hole in the top of an old gate-post, 4 ft. 6 in. from the ground; and with regard to the other, a Robin built early in the year in a large hole in a wall five feet from the ground, and safely reared its young. Shortly after the nest was appropriated by a Willow-Wren, which domed over the old nest, and plentifully lined it with feathers. This bird also safely reared her young. I saw all nests, eggs, and old birds, and a friend took excellent photographs of the bird that built in the Robin's nest, feeding her young, in various positions.—Oxley Grabham (Heworth, York).
"Chiffchaff building on the top of small Yew and Box Trees."—In this district Chiffchaffs rarely, if ever, build on the ground; I have found upwards of thirty nests in a season, but have never seen one quite on the ground, although sometimes it is only raised a few inches in brambles or other low-growing plants. I have many times seen nests in box trees from three to six feet high, but have only once found a Willow-Wren's nest that was not on the ground; in this case I caught the female, and sent it to Mr. Dresser to be quite sure of my identification. It has
