BIRDS. 39 



behind (in a few cases, back of tarsus without ridge, and formed 

 of a few scutellae distinct from those lapping over the front ) ; first 

 primary short, spurious or wanting, if present, not more than 

 two-thirds of the longest ; musical apparatus highly developed. 

 * Primaries 10 ; the first short or spurious. 

 f Tarsus booted ; rictus with bristles. 

 a. Middle toe quite free from inner; birds of moderate size, 



length more than 6. 



&. Wings moderate, not reaching when folded beyond the 

 middle of tail, and not more than one-third longer 

 than tail ; tip of wing formed by 3d to 6th quill ; no 



blue TURDID^E, 18. 



lib. Wings very long, pointed, reaching beyond middle of 



tail, and more than half longer; tip of wing formed 



by 2d to 4th quills ; ours chiefly blue. SAXICOLID^E, 19. 



act. Middle and inner toes connected at base ; small, length 



less than 5 . SYLVIID.E, 20. 



ft Tarsus scutellate in front. 



c. Nostrils concealed by tufts of antrorse, bristly feathers. 

 d. First primary not more than half length of second ; bill 



not notched ; length less than 8. 



e. Bill as long as head ; wings pointed, much longer than 

 tail. . . . . . . SiTTnxas, 22. 



ee. Bill much shorter than head ; wings about as long as 



tail PARTD^E, 21. 



dd. First primary more than half length of second ; bill 

 usually notched, the bristly nasal feathers branched to 

 their tips ; large, length more than 8. CORVID^E, 35. 

 cc. Nostrils exposed (rarely slightly overhung). 

 /. Bill distinctly notched near its tip, often hooked. 



g. Tail longer than wings ; general color gray or ashy- 

 brown. 



7i. Bill very stout, compressed, strongly notched, toothed 

 and abruptly hooked at tip ; large, length 8 to 9. 



LANIID^E, 32. 



Wi. Bill more slender, not deeply notched nor abruptly 

 hooked ; length 8 to 10. . . TURDID^E, 18. 



