The second suborder of the Ciconiiformes, or Stork-like birds, embraces the Herons and their immediate relatives. They are at once distinguished from the group last considered by their very long legs, which adapt them to wading rather than swimming, although they can all swim to a limited extent when forced to do so. A further distinguishing mark is afforded by the fact that the toes are not completely webbed, and that powder-downs are always present. The sub-order may perhaps be best divided into four families as follows: the Ardeidae, which includes the Herons, Egrets, Bitterns, etc.; the Cochleariidae, including the American Boat-bills; the Balaenicipitidae, embracing the anomalous Shoe-bill; and the Scopidae, for the almost equally remarkable Umbrette, the latter two being African.