"We began to be ver y curious when teacheropened the mandibles and pointed out to us, along the edge of the upper one, a row of fifty or sixty projecting points. These form a sort of stiff fringe, something like the teeth of a comb. The tongue, which is large and fleshy, fills the whole of the mouth. All round the edge of the tongue there is a fringe, something like that which hangs from the mandible.""How very strange," said Norah. "I can"t think yet what the meaning of it all can be.""When the mouth is shut," Fred went on, "the fringe on the edge of the tongue and that hanging down from the mandible fit into each other.
"These birds find their food by groping in the mud, with their shovel-like bills. The mud and dirty water are strained out at the sides of the mouth, but the insects, grubs, and worms, and whatever is fit for food are held back by the fringed edges as in a trap.
"You see, ducks live on grubs and worms, like thewoodpecker, but they catch them in a different way.
