The heronries of the southern portions of the United States are often of such extraordinary size as to astonish the passing traveller. I confess that I myself might have been as sceptical on this point as some who, having been accustomed to find in all places the Heron to be a solitary bird, cannot be prevailed on to believe the contrary, had I not seen with my own eyes the vast multitudes of individuals of different species breeding together in peace in certain favourable localities. Such persons may be excused from giving that credit to my account of the Passenger Pigeon which posterity will, I trust, accord to it. The nest of the Blue Heron, wherever situated, is loosely formed of dry sticks, sometimes intermixed with green leaves of various trees, and with grass or moss, according as these materials happen to be plentiful in the neighbourhood. It is nearly flat, and can scarcely be said to have a regular lining. Sometimes you see a solitary nest fixed on a cactus, a bush, or a tree; but a little beyond this you may observe from six to ten, placed almost as closely together as you would have put them had you measured out the space necessary for containing them. Some are seen low over the water, while others are placed high; for, like the rest of its tribe, this species is rather fond of placing its tenement over or near the liquid element. The eggs are usually three, rarely four; and I have never found a nest of this species containing five eggs, as is stated by WILSON, who, probably found a nest of the Green Heron containing that number among others of the present species. They measure an inch and three quarters in length, by an inch and a quarter in breadth, being about the size of those of _Ardea candidissima_, though rather more elongated, and precisely of the same colour.