ARTIFICIAL KEY TO THE FAMILIES. 231 



ARTIFICIAL KEY TO THE FAMILIES. 



TOES 3, — 2 IN FKONT, 1 BEHIND PlOID^ 477 



TOES 3, — 3 IN FKONT. (Go to II.) 



TOES 4, — 2 IN FRONT, 2 BEHIND. (Go tO HI.) 



TOES 4, —3 IN FEONT, 1 BEHIND. (Go tO IV.) 



II. [Toes 3, — 3 in front.] 



Toes — completely webbed. NostrilB — tubular (Albatrosses) PEOCiELLABiiD.ffi: 773 



— not tubular (Auks, &o.) ALon>.ffii 797 



— incompletely or not webbed. Legs — about as long as wings. Bill subulate (Stilt) BE0UBTiB0STSiD.ffi 609 



— much shorter than wings (go to a). 



(a) TaisuB — scutellate in front, about as long as bill (Sanderling) SoOLOPAOiD.a! 614 



— reticulate in front — shorter than red chisel-like bill (Oyster-oatoher) . Ka;mATOPODiD.a; 606 



— longer than bill (Plovers) Chaeadeiidje 597 



III. [Toes 4, — 2 in front, 2 behind.] 



Bill — cored and strongly hooked. Tarsus granulated (Parrot) PsiTTAciiD.a; 496 



— not cered J inner hind toe — 3-jointed ; Plumage iridescent (Trogon) TROGONiDa: 468 



— 2-jointed ; — tail of — 8 or 10 soft feathers (Cuckoos, &c. ) . . Cxjcvudm 470 

 — 12 (apparently only 10) rigid acuminate feathers 



(Woodpeckers) .... P101D.S! 477 



IV. [Toes 4, — 3 in front, 1 behind.] 



Hind toe — inserted above the level op 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 ba/rely elevated). (Go to A.) 



— palmate (3 front toes full-webbed, hind toe welt up, simple or lobed or caimected by slight webbi/ng to 



base only ofiimer toe). (Go to B.) 



— lobate {3 front toes partly webbed or not, and conspicwmsly bordered with plam or scalloped mem/- 



branes; hind toe free, and simple or lobed). (Go to C.) 



— SEMIPALMATB (2, or 3, front toes webbed at base only by small yet evident membrame ; hind toe well up, 



simple). (Go to D.) 



— SIMPLE (front toes with tw evident membra/nes ; hind toe well up, simple). (Go to E.) 



(A.) Tarsus — feathered, partly ; tail deeply forked; bill epignathous (Frigate-bird) .... Taohypetid^ 730 

 — naked; bill — > tail.'hoolced at tip, furnished with enormous pouch (Pelicans) PELECANiDiB 721 

 — < tail; throat — feathered; middle tail feathers filamentous (Tropic-biids) 



Phaethontid^ 731 

 — naked; tail— pointed, soft; tomiasubeerrate(Gannets) SuLiD.ai 720 

 —rounded, stiff; bill — paragnathous (Anhinga) 



Plotid* 729 

 — epignathous (Cormorants) 



Phalaorocoraoid.«: 723 



