I have never heard that there is any real difference in size, but hen blackbirds appear bigger than cocks, just as young gulls in immature plumage seem larger than old ones. I suppose the different colour has something to do with it, and perhaps the cock's feathers are more closely set than the hen's. My wife told me that she had seen one evening in September (1907) 16 blackbirds on the tennis ground together. This seems perhaps rather a large order, as they say, but in the following September I counted nine myself, to the best of my belief, all of them cocks. IV. CHATS, ROBINS AND WARBLERS. In spring, and again in autumn, wheatears pass through, and may be seen about for several days at a time. In April and May, 1908, a pair stayed so long in some rough ground near the bank of the Ship Canal that I thought they might be going to take up their quarters there for the season, but by May 31st they had disappeared. We always have a fair number of whinchats in the meadows, and hardly a year passes without seeing them on the grass in the garden itself. One very wet summer, when in the low-lying lands the haycocks were standing for days surrounded by water, I remember being struck by the number of whinchats to be seen perching and chatting first on one haycock and then on another. Though whinchats are so comparatively common, and their usual note, exactly like the knocking of two pebbles together, is constantly heard, their pretty little song, a cadence of a few notes repeated over and over again, I do not remember to have noticed here. Only once have I seen a stonechat in the neighbourhood of this garden. This was in October, 1890. On the opposite side of the river the land had been raised by material excavated in the making of the Ship Canal, and was at that time wild and covered with a strong growth of all kinds of weeds. It was on a wire fence that ran along this bank that I saw the bright little bird. And there, with a curious pendulum-like movement of its tail, it continued to sit for a considerable time, giving me ample opportunity to study it leisurely through a field-glass. Though redstarts are not uncommon in Dunham Park a few miles away, only once have I seen one in the garden, in August, 1894. It stayed for several days, and was never far away from the place where I first saw it. I noticed that other birds who are at home here, wagtails especially, seemed to look upon it as an interloper and resented its intrusion. One of the first things that I remember about the natural history of Warburton is a brood of four white--or more strictly speaking, cream-coloured--robins that were hatched in a neighbouring garden in 1872. They were jealously watched over by the owner of the garden, and I often saw two of them until the autumn. Then they must either have been taken (and many people were after them) or have moulted to the ordinary robin colours, for we saw them no more.