Note: The red-breasted merganser ({Merganser serrator})
inhabits both hemispheres. It is called also {sawbill},
{harle}, and {sheldrake}. The American merganser ({M.
Americanus}.) and the hooded merganser ({Lophodytes
cucullatus}) are well-known species.
{White merganser}, the smew or white nun.
Note: It has the head and neck greenish black, the breast,
sides, and forward part of the back brown, the
shoulders and middle of belly black, the speculum
green, and the bill and frontal bright red. Called also
{shelduck}, {shellduck}, {sheldfowl}, {skeelduck},
{bergander}, {burrow duck}, and {links goose}.
Note: The Australian sheldrake ({Tadorna radja}) has the
head, neck, breast, flanks, and wing coverts white, the
upper part of the back and a band on the breast deep
chestnut, and the back and tail black. The chestnut
sheldrake of Australia ({Casarca tadornoides}) is
varied with black and chestnut, and has a dark green
head and neck. The ruddy sheldrake, or Braminy duck
({C. rutila}), and the white-winged sheldrake ({C.
leucoptera}), are related Asiatic species.
2. Any one of the American mergansers.
Note: The name is also loosely applied to other ducks, as the
canvasback, and the shoveler.