ARTIFICIAL KEY TO THE FAMILIES. 
231 
ARTIFICIAL KEY TO THE FAMILIES. 
TOES 3, — 2 IN FRONT, 1 BEHIND 
TOES 3, — 3 IN FRONT. (Go to II.) 
TOES 4,-2 IN FRONT, 2 BEHIND. (Go tO III.) 
TOES 4, — 3 IN FRONT, 1 BEHIND. (Go tO IV.) 
Page 
PlCiD^ 477 
II. [Toes 3, — 3 in front.] 
Toes — completely webbed. Nostrils — tubular (Albatrosses) Procellariid^ 773 
— not tubular (Auks, &c.) Alcid^ 797 
— incompletely or not webbed. Legs — about as long as wings. Bill subulate (Stilt) Recurvirostrid.*: 609 
— mucli shorter than wings (go to a). 
(a) Tarsus — scutellate in front, about as long as bill (Sanderling) Scolopacid^ 614 
— reticulate in front — shorter than red chisel-like bill (Oyster-catcher) . H^matopodid^ 606 
— longer than bill (Plovers) CnARADRilDiE 597 
III. [Toes 4, — 2 in front, 2 behind.] 
Bill — cered and strongly hooked. Tarsus granulated (Parrot) Psittaoid^ 496 
— not cered; inner hind toe — 3-jointed ; Plumage iridescent (Trogon) Trogonid^ 468 
— 2-jointed; — tail of — 8 or 10 soft feathers (Cuckoos, «&;c.) . . Cuculidje 470 
— 12 (apparently only 10) rigid acuminate feathers 
(Woodpeckers) PlciD^ 477 
IV. [Toes 4, — 3 in front, 1 behind.] 
Hind toe — inserted above the level of the rest (and always shorter than the shortest 
front toe). (Go to A.) 
— NOT INSERTED ABOVE THE LEVEL OF THE REST (AND GENERALLY BUT NOT ALWAYS NOT 
shorter than the SHORTEST FRONT TOE). (Go tO B.) 
A. [The hind toe elevated.] 
Feet — totipalmate {all 4 toes webbed; hind toe semi-lateral and barely elevated). (Go to A.) 
— palmate {3 front toes full-webbed, hind toe well up, simple or lobed or connected by slight webbing to 
base onbj of inner toe). (Go to B.) 
— lobate (3 front toes partly webbed or not, and conspicuously bordered with plain or scalloped mem- 
branes; hind toe free, and simple or lobed). (Go to C.) 
— semipalmate (2, or Z, front toes webbed at base only by small yet evident membrane ; hind toe well up, 
simple). (Go to D.) 
— SIMPLE (front toes with no evident membranes ; hind toe well up, simple). (Go to E.) 
i\.) Tarsus — feathered, partly; tail deeply forked; bill epignathous (Frigate-bird) . . . . Tachypetid^ 730 
— naked; biU — > tail, hooked at tip, furnished with enormous pouch (Pelicans) Peleoanid^ 721 
— < tail; throat — feathered; middle tail feathers filamentous (Tropic-birds) 
Phaethontid^ 731 
— naked ; tail — pointed, soft ; tomia subserrate (Gannets) Sulid^e 720 
— rounded, stiff; bill — paragnathous (Anhinga) 
PLOTID.S: 729 
— epignathous (Cormorants) 
PHALACROCORACIDiE 723 
