Key to the Families 



Order i. PASSERIFORMES. Sparrow-like Birds. 



Birds having feet adapted to perching, with first toe (hallux, or thumb) well developed, irreversible, and definitely 

 opposed to the remaining three, which are likewise irreversible; primaries 9 or 10, secondaries more than 6; rectrices 

 12 (or, rarely, 10); bill various as to shape but always horny throughout, never provided with cere or deciduous parts 

 or other seasonal modifications. Pygmy to raven size. Eggs 1-12, usually 3-5, exhibiting the widest range of color 

 and markings. 



Passerine birds represent the highest development of the avian type and comprise nearly one-half of the known 

 species of birds. Because of this high degree of differentiation within narrow structural limits, practical expediency 

 has led us to exalt to "family" rank groups which are actually no better than genera. Furthermore, the most obvious 

 distinclions of "character" which assuredly do separate groups, when reduced to somatic, or structural, terms must 

 seem highly artificial. To speak, then, "above the book," birds of this group have become so highly personalized 

 that a merely physical description is inadequate. 



Discussion of higher groups within the Passeriformes, whether suborders or superfamilies, is beside our purpose; 

 but it is well for Californians to remember that the Flycatchers, Order Tyrannidiz, are set off from the remaining 

 Passerine families of California, by reason of differently arranged syringeal muscles, which render their voices less 

 varied or tuneful. 



I. Back of tarsus rounded like the front. 



A. Bill hooked at tip. 



B. Bill not hooked. 



II. Back of tarsus a sharpened ridge. 



A. With 9 primaries. 



1. Tertiaries conspicuously elongated. 



2. Tertiaries not conspicuously elongated. 



a. Bill very short; wings long and pointed. 



b. Bill moderate; wings moderate. 

 (1). With angle of commissure (formed by opened mandi 



(a). Angle abruptly deflected downward; bill cone- 

 shaped, 

 (b). Angle less sharply bent; bill usually more slender. 

 (2). Angle of commissure not bent, 

 (a). Bill notched near tip. 

 (b). Bill simple. 



B. With 10 primaries. 



1. Bill hooked at tip. 



a. Head crested, uncination moderate. 



b. Head not crested, uncination more sharply defined. 

 (1). Small; under 6.50 inches long. 



(2). Large; over 8.50 inches long. 



2. Bill not hooked. 



a. Tarsus divided into scales (acrotarsium scutellate). 

 (1). Tail feathers stiffened, pointed at tip. 



(2). Tail feathers normal. 



(a). Nostrils entirely covered by forward-projecting 



(a 1 ). Larger; feathers covering nostrils bristly 



(b 1 ). Smaller; feathers over nostrils not bristly, 

 (b). Nostrils partly covered by feathers, 

 (c). Nostrils bare. 



(a 1 ). Basal phalanges of anterior toes fully adherent. 



(b 1 ). Basal phalanges nearly or quite free. 



b. Anterior tarsal covering nearly or completely united 



(acrotarsium booted). 

 (1). With rictal bristles (at corner of mouth), 

 (a). Bill short, flattened and deeply cleft. 

 (b). Bill normal. 



(a 1 ). Wings long and pointed, over 3.00 in length: 

 (b 1 ) . Wings moderate with rounded tip, not over 2.50 



in length. 

 (c 1 ). Wings relatively short, very much rounded. 

 (2). Without rictal bristles. 



Fam. 22. Tyrannidae, Flycatchers. 

 Fam. 21. Alaudidje, Larks. 



Fam. 20. Motacillidje, Wagtails, Pipits. 



Fam. 6. Hirundinid^e, Swallows. 



bles) bent near base. 



Fam. 3. Fringillidje, Sparrows. 

 Fam. 2. Icterid;£, Troupials, etc. 



Fam. 4. Tanagridje, Tanagers. 



Fam. 5. Mniotiltid^e, Wood Warblers. 



Fam. 7. Ampelidje, Waxwings. 



Fam. 9. Vireonid/e, Vireos. 

 Fam. 10. Laniidje, Shrikes. 



Fam. 13. Certhtid^, Creepers. 



frontal feathers. 



Fam. I. Corvidje, Crows, Jays. 

 Fam. 11. Paridje, Titmice. 

 Fam. 12. Sittid.'e, Nuthatches. 



Fam. 14. Troglodytidje, Wrens. 



Fam. 15. Mimid^e, Mockingbirds, Thrashers. 



Fam. 8. Ptilogonatidje, Silky Flycatchers. 



Fam. 17. Turdid;e, Thrushes. 



Fam. 18. Sylviid^e, Old World Warblers. 

 Fam. 19. Cham^eidje, Wren-Tits. 

 Fam. 16. Cinclid^e, Dippers. 



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