g1. Hind toe well developed and inserted on the level of the anterior toes; claws not excessively lengthened; loral or orbital region or both naked ... Ardeiformes (p. 157) g2. Hind toe if present, small and inserted above the level of the rest; or else size of bird small (less than 1 meter), loral and orbital regions fully feathered and middle claw not pectinate. h1. If more than 1 meter long the hind toe short and elevated; if less than 1 meter long the hind toe not elevated. i1. Size very large; hind toe small and elevated. ... Gruiformes (p. 155) i2. Size medium to small; hind toe not elevated. ... Ralliformes (p. 65) h2. Less than 1 meter long, usually much less; the hind toe if present, short and elevated, or if long the claws excessively long and wings spurred ... Charadriiformes (p. 98) f2. Lower portion of thighs feathered; or else middle and outer toes united for at least half their length, the bill if lengthened not grooved along the side. g1. Bill strongly hooked and with a distinct cere at base of upper mandible. h1. Toes three in front; or else outer toe reversible; claws sharp and powerful. i1. No facial disk of modified feathers; plumage normal, compact; nostrils generally not concealed by bristles. ... Accipitriformes (p. 210) i2. Eyes surrounded by a disk of modified feathers; plumage soft and fluffy; nostrils usually concealed by stiff bristles. ... Strigiformes (p. 249) h2. Toes two in front and two behind, the outer toe permanently reversed; claws small and dull ... Psittaciformes (p. 272) g2. Bill not strongly hooked and without a cere at base of upper mandible. h1. Hind toe small and elevated ... Galliformes (p. 9) h2. Hind toe or toes well developed and on the same level as the anterior toes. i1. Upper mandible with a soft swollen base. ... Columbiformes (p. 23) i2. Bill without a soft swollen base. j1. Toes two in front, two behind; rarely two in front and one behind, then the bill straight and the rectrices stiff and pointed. k1. Two toes in front united for their basal joint. l1. Inner toe reversed, tail graduated ... Trogones (p. 362) l2. Outer toe reversed, tail nearly square. ... Scansores (p. 389) k2. Two toes in front perfectly free.