Sub-order 2. Ardeae.—Piscivorous, nidicolous, waders; with complicated hypotarsus and with long cervical apteria. Ardeidae, cosmopolitan; including Cancroma, Neotropical, Balaeniceps, Scopidae, Ethiopian. Proherodius, Eocene of England.
Sub-order 3. Ciconiae.—Zoophagous, nidicolous, waders; with simple hypotarsus and without cervical apteria. Cosmopolitan. Ciconiidae, storks. Ibidae, ibises and spoonbills. Propelargus, Oligocene.
Sub-order 4. Phoenicopteri.—Flamingos. Nidifugous, waders; with simple hypotarsus and without cervical apteria. Front toes completely webbed; hallux very short or absent; feed chiefly on small aquatic invertebrates. Phoenicopterus, cosmopolitan. Oligocene Elornis and, allied, Palaelodus.
6. Order Anseriformes.—Desmognathous, nidifugous; with two pairs of sterno-tracheal muscles, with complete basipterygoid processes and with a penis.
Sub-order 1. Palamedeae.—Screamers. Ribs without uncinate processes. Hypotarsus simple. Neotropical. Chauna, Palamedea.
Sub-order 2. Anseres.—Family Anatidae. Hypotarsus complex. Anser, Anas, Cygnus, since Miocene. Cnemiornis, Pleistocene, New Zealand, flightless.
7. Order Falconiformes.—Birds of prey. Carnivorous, desmognathous, nidicolous, without functional caeca. Terrestrial, aerial.
Sub-order 1. Cathartae.—American vultures. With nares perviae. Cathartes, turkey buzzards, Sarcorhamphus gryphus, condor Gypagus papa, king vulture.
Sub-order 2. Accipitres.—With nares imperviae. Serpentariidae, secretary-bird, Ethiopian; Miocene, France. Vulturidae, Old World vultures, excluding Australia. Falconidae, cosmopolitan, since the Eocene. Harpagornis, Pleistocene, New Zealand; Lithornis, Eocene, England. Pandionidae, ospreys or fish hawks, cosmopolitan.
8. Order Tinamiformes.—Nidifugous, with incisura ischiadica, without pygostyle. Herbivorous, terrestrial, neotropical. Crypturi, tinamous.