Instinct in Birds

I READ with special interest the letter signed ``Wm. Brown'' in NATURE of the 15th (p. 56). Iregret I cannot see the letter to which it refers. My excuse for intruding on your limited space is that I have something to say about a magpie's nest. My text is words in Mr. Brown's letter, ``I have often seen the nest shot down.'' Some years ago seeing a magpie fly from her nest I climbed the tree to see what was in it. I found six eggs, but not magbies'. They were starlings' eggs on which the magpie was sitting. I visited the tree several times, and always found the magpie sitting on the starlings' eggs. To my great regret, on finally coming to see how the magpie and her foster brood were getting on, I found a shot-hole through the nest, and magpie and eggs knocked to pieces.