The fourth family of Wading Birds is classified by a Latin name meaning
knife-shaped bill, although the different Birds found in this group have
bills of many curious forms; they are all long, sharp-edged and very
strong. These Birds live along the edges of marshes and the banks of
rivers, and their long legs have great strength; so that many of them
are able to stand on one leg for hours together. This faculty is said to
be due to a curious arrangement in the knee—a sort of knot which
stiffens the ligaments of the knee, forming a kind of catch similar to
the spring of a knife.
The principal species of this family are the various Storks—including
the Argala or Adjutant, the Marabou and Jabiru—the Spoonbill, Boatbill,
Heron and the different Cranes—including the Egret and the Bittern.