CLASS  AVES I . Sub-class Archaeornithes.—The three fingers and their metacarpals remain

separate, each with a claw . Well-developed remiges . Both jaws with alveolar teeth . Amphicoelous . Caudal vertebrae more than thirteen, without a pygostyle, but with about twelve pairs of rectrices . Archaeopteryx, A. lithographica, s. macroura, two specimens from the upper Oolite of Solenhofen, Bavaria . II . Sub-class Neornithes.—Metacarpals fused . Second finger the longest . Not more than thirteen caudal vertebrae . I .

Division RATITAE.—Terrestrial, flightless . Without sternal keel . Quadrate bone with single proximal knob . With-out pygostyle . Coracoid and scapula fused . Compound rhamphotheca . Adult without apteria . With copulatory organ . A collective polyphyletic or heterogeneous group, originally cosmopolitan; with certainty existing since the Miocene . 1 . Order Struthiones.—With pubic symphysis . Two toes only, third and fourth .

Struthio,

ostrich, Pliocene of Samos and of north-west India, now Africa and Arabia . 2 . Order Rheae.—With long ischiadic symphysis . Three toes . Mesembriornis, Miocene or Pliocene of Argentina . Rhea, South America . 3 . Order Casuarii.—Three toes . Aftershaft as long as the other I half . Casuarius and Dromaeus, Australian . Hypselornis, Pliocene of Sivalik Hills . 4 .

Order Apteryges.—Four toes .

Bill long and slender . Apteryx, New Zealand . 5, Order Dinornithes.—Three or four toes . Bill short . Anterior limbs extremely reduced . Dinornis, numerous species, recently extinct, New Zealand . 6 . Order Aepyornithes . Aenyornis, recently extinct, Madagascar . To the Ratitae belong possibly also the imperfectly known Diatryma, Eocene of New Mexico, Gastornis and Dasornis, Eocene of Europe, Genyornis, Pleistocene of Australia . II .

Division

ODONTOLcAE.--Marine, flightless, without sternal keel . Upper and lower jaws with teeth in furrows . Cretaceous epoch . Enaliornis, England, vertebrae chiefly biconcave; Hesperornis, North America, vertebrae heterocoelous . 1 . Order Ichthyomithes.—Power of flight well developed . Vertebrae still amphicoelous . With small pygostyle . Incisura ischiadica . With alveolar teeth . Cretaceous of Kansas . Ichthyornis, Apatornis .

2 . Order Colymbiformes.—Plantigrade, nidifugous, aquatic . All toes webbed, fourth largest, hallux short; metatarsus laterally compressed ;

tibia with high, pyramidal crest . Bill straight, pointed, with simple sheath . Sub-order 1 . COLYMBI, Divers . Front toes completely webbed . Holarctic . Colymbus . Sub-order 2 . PODICIPEDES, Grebes . Toes lobated .

Cosmopolitan . 3 . Order Sphenisciformes.—Nidicolous, marine . Fiightless, wings transformed into

rowing paddles . SPHENISCI, penguins . Antarctic and southern temperate coasts . Since the Eocene . 4 . Order Procellariiformes.—Well flying, pelagic, nidicolous . Hallux absent or vestigial . Rhamphotheca compound . Cosmopolitan .

TUBINARES, petrels and albatrosses . 5 . Order Ciconiiformes.—Swimmers or waders . Desmognathous, without basipterygoid processes; with one pair of sternotracheal muscles . Sub-order 1 . STEGANOPODES.— Well flying, aquatic, nidicolous; with all the four toes webbed together . Rhamphotheca compound; cosmopolitan .

Phaethon, tropic-bird; Sula, gannet; Phalacrocorax, cormorant and Plotus, snake-bird; Fregata, frigate-bird; Pelecanus . Here also Pelagornis, Miocene of France; Argillornis and probably Odontopteryx from the London Clay . 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 . S . Order Tinamiformes.—Nidifugous, with incisura ischiadica, without pygostyle . Herbivorous, terrestrial, neotropical . Crypturi, tinamous . 9 . Order Galliformes.—Schizognathous, herbivorous, terrestrial . With ten functional remiges .

With strong spinae sterni . Sub-order I . MEsITEs.—Without basipterygoid processes, and with large

spina interna . Mesites, Madagascar . Sub-order 2 . TURNICES.—Hemipodes or button-quails . Nidifugous; vomer large; sternum without processus obliqui . Hallux absent or vestigial . Old World . Turnix, Pedionomus . Sub-order 3 . GALLI.—With large spina communis, and with large processus obliqui .

Hallux functional . Mega- podiidae, Australian region . Cracidae, curassows and guans, neotropical . Gallidae, cosmopolitan . Sub-order 4 . OPIsTUocoMI.—Arboreal, with long spina externa; without basipterygoid processes . Opisthocomus hoatzin,

Guiana, Venezuela and Amazon countries . so . Order Gruiformes . Legs of the wading type . Without basipterygoid processes . Without spina interna .

Nidifugous . Essentially schizognathous . Ralhdae, cosmopolitan, since Oligocene . Rallus, Fulica, Ocydromus, &c., Gallinula nesiotis,

Tristan d'Acunha, flightless . Notornis, New Zealand, flight-less, nearly extinct . Aptornis, New Zealand, flightless, extinct . Aphanapteryx (Mauritius) = Erythromachus (Rodriguez) = Diaphorapteryx (Chatham Island), flightless and recently extinct . Gypsornis, upper Eocene, France . Gruidae, cranes, cosmopolitan, allied Phororhacos, Tertiary of Argentina . Dicholophidae, cariamas, neotropical . Otididae, bustards, Old World . Rhinochetidae, kagus, New Caledonia .

Eurypygidae,

sun-bittern, neotropical . Heliornithidae, finfoots, tropical . I t . Order Charadriiformes.—Schizognathous . With eleven remiges, of which the terminal very short . Aquinto-cubital . Spinae sterni short, separate . Sub-order 1 . LIMIcoLAE.—Nidifugous, without spina interna sterni . Hypotarsus complicated . Charadrisdae, plovers . Chionididae, sheath-bill .

Glareolidae, wading swallows and coursers . Thinocorythidae,

seed-snipes . Oedicnemididae, thick-knees . Parridae . Sub-order 2 . LARI.—Aquatic, vomer complete . Without basipterygoid processes . Front toes webbed; hallux small or absent . Large supraorbital glands . Since Miocene . Laridae, gulls, cosmopolitan . Alcidae, auks, northern half of periarctic region .

Sub-order 3 . PTERocLEs.—Sand-

grouse . Nidifugous . Vomer vestigial . With large crop and caeca . Hallux vestigial or absent since Oligocene . Africa to India, and Siberia . Pterocles and Syrrhaptes . Sub-order 4 . COLUMBAE.—Pigeons . Nidicolous . Vomer vestigial .

With large crop, vestigial caeca . Columbidae, cosmopolitan, since Miocene . Dididae, flightless, recently extinct . Did us,

dodo, Mauritius . Pezophaps, solitaire, Rodriguez . 12 . Order Cuculiformes.—Desmognathous, nidicolous; zygodactylous, or with the outer toe reversible . Sub-order t . Comm.—Cuckoos . Quinto-cubital . Cuculidae, cosmopolitan . Musophagidae, plantain-eaters and touracos, Ethiopian since Miocene .

Sub-order 2 . PSITTACI.—Parrots . Zygodactylous; aquintocubital . Cosmopolitan, chiefly tropical . Trichoglossidae, lories, Austro-Malayan .

Nestor, New Zealand . Cyclopsittacus, Eos, Lorius, &c . Psittacidae, tongue smooth, incl . Stringops . 13 . Order Coraciiformes.—Nidicolous . Nares imperviae, holorhinal .

Downs restricted to the apteria or absent . Thirteen to fifteen cervical vertebrae . Mostly desmognathous . Deep plantar tendons connected with each other . Sub-order I . CoRACIAE.—Either (I) with long spina externa sterni, Coraciidae, rollers, Old World . Momotidae, neotropical, motmots and todies . Alcedinidae, king-fishers, cosmopolitan or (2) with long spina communis . Meropidae, bee-eaters, Old World . Upupidae, Upupinae, hoopoes: palaearctic and palaeotropical . Bucerotinae, hornbills, palaeotropical; Irrisorinae, woodhoopoes, Ethiopian . Sub-order 2 .

STRIGES.—Owls . Outer toe reversible . Schizognathous . Long caeca . Flexor tendons normal . Hypotarsus simple . Cosmopolitan . Sub-order . 3, CAPRIMuLGI.—Nightjars . Nocturnal . With gaping mouth . Ten remiges and ten rectrices .

Spinae sterni vestigial . Caeca functional . Steatornithidae, Steatornis, oil-bird or

guacharo, South America . Podargidae, Australasian, Caprimulgidae, cosmopolitan . Sub-order 4 . CYPsELI.—Tenth terminal remex the longest . With short spinae sterni . Without caeca . Cypselidae, swifts, cosmopolitan . Trochilidae, humming-birds, American . Sub-order 5 . CoLII.—Mouse-birds .

First and fourth toes reversible . Ethiopian . Sub-order 6 . TROGONES.—Trogons . Heterodactyle, first and second toes directed forwards, third and fourth backwards . Tropical .

Trogon gallicus, Miocene of France . Sub-order 7 . PIc1.—Zygodactylous . Tendon of the flexor hallucis longus muscle sending a strong vinculum to that of the flexor profundus muscle, the tendon of which goes to the third toe only . Galbulidae, puff-birds and jacamars, neotropical . Capilonidae, barbets, tropical .

Rhamphastidae, toucans, neotropical . Picidae,

wood-peckers, cosmopolitan, excepting Madagascar and Australian region . 14 . Order Passeriformes.—Nidicolous . Aegithognathous, without basipterygoid processes . Spina externa sterni large, spina interna absent . Quinto-cubital, toes normal . Apparently since the upper Eocene . Sub-order I . PASSERES ANISOMYODAE.—SyrinX muscles entirely lateral or attached to the dorsal or ventral corners of the bronchial semi-rings . (i) Subclamatores . Deep plantar tendons connected by a vinculum .

Eurylaemidae, broad-bills,

Indian and Indo-Malayan . (2) Clamatores . Deep flexor tendons not connected . Pittidae, palaeotropical . Xenicidae, New Zealand . Tyrannidae, American, Formicariidae, Pteroptochidae, neotropical . Sub-order 2 . PASSERES DIACROMYODAE.—Syrinx muscles of either side attached to the dorsal and ventral corners of the rings . Hallux strong, with a large claw . (i) Suboscines with Menura, lyre-bird, and Atrichia, scrub-bird, in Australia . (2) Oscines, the true singing-birds, with more than 5000 recent species, are mostly divided into some thirty " families," few of which can be defined . The fourteen orders of the Carinatae are further congregated into four "Legions":- 1 .

COLYMBOMORPHAE = Ichthyornithes + Colymbiformes + Sphenisciformes + Procellariiformes . II . PELARGOMORPHAE = Ciconiiformes + Anseriformes + Falconiformes . IV . CORACIOMORPHAE = Cuculiformes + Coraciiformes + Passeriformes . These four legions are again combined into two " Brigades," the first of which comprises the first and second legions, while the second

brigade contains the third and fourth legions . Thus the whole classification becomes a rounded-off phylogenetic system, which, at least in its broad outlines, seems to approach the natural system, the ideal goal of the scientific ornithologist .