I have often spoken of the great differences as to size and colour that are observed in birds of the same species, and which have frequently given rise to mistakes, insomuch that the male, the female, and the young, have been considered as so many distinct species. The Long-legged Sandpiper has been treated in this manner, and has latterly reappeared under the name of _Tringa Douglassii_, in the Fauna Boreali-Americana of my friends RICHARDSON and SWAINSON. BONAPARTE was, in truth, the first who described this bird; and although some differences might be found between his specimen and the _one_ described in the work just mentioned, they are trifling compared with those which I have observed between seven or eight individuals all procured from the same flock at a single shot. It is strange that neither BONAPARTE nor SWAINSON have mentioned the sex of their specimen. On the morning of the 4th of April 1837, while seated among the drift wood that had accumulated on the southern shore of the island of Barataria, forty miles from the south-west pass of the Mississippi, and occupied in observing some Pelicans, I saw a flock of about thirty Long-legged Sandpipers alight within ten steps of me, near the water. They immediately scattered, following the margin of the retiring and advancing waves, in search of food, which I could see them procure by probing the wet sand in the manner of Curlews, that is, to the full length of their bill, holding it for a short time in the sand, as if engaged in sucking up what they found. In this way they continued feeding on an extended line of shore of about thirty yards, and it was pleasing to see the alacrity with which they simultaneously advanced and retreated, according to the motions of the water. In about three quarters of an hour, during all which time I had watched them with attention, they removed a few yards beyond the highest wash of the waves, huddled close together, and began to plume and cleanse themselves. All of a sudden they ceased their occupation, stood still, and several of them emitted a sharp _tweet-tweet_, somewhat resembling the notes of _Totanus solitarius_; immediately after which seven birds of the same species passed close to me, and alighted near those which I had already watched. They at once began to feed, and as I thought that the first flock might join them, and that I might lose the opportunity of procuring specimens, in sufficient number, I fired and killed eleven. The rest flew off, and were joined by the second group, the whole flying to windward in a compact body, and emitting every now and then their sharp _tweet_, _tweet_, until out of sight and hearing. My son JOHN obtained several of these birds on the same island while they were feeding on the margins of a fresh-water pond; and we saw them on almost every island and bay on our way to the Texas, where we also procured some on Galveston Island.