The Old World is the home also of the Mute Swan (C. Olor), so named from the fact that in the domesticated or semi-domesticated state it is without voice, though in its purely wild state it is said by Naumann to have a loud, trumpet-like note, at least during the breeding season. It belongs to a different group from the species already described in possessing a prominent knob at the base of the bill, and in the absence of convolutions of the windpipe within the breast-bone. It is a large bird, often reaching a length of five feet,and like the others is pure white. In the wild state it is found in summer from north and central Europe to central Asia, and in winter south to northern India and the Caspian and Mediterranean seas. It has apparently been in domestication in England since about the close of the twelfth century, and has now been taken throughout the world as an ornamental bird on lakes and ponds in parks and estates. There is a large swannery near Weymouth, England, which in 1880 numbered about 800 birds, where they breed freely and may possibly mix with the really wild birds which appear at intervals on the English coast.