BIRDS. 41 



A-/-. Nostrils concealed by bristly feathers , tarsus scutellate 



behind; hind claw long and nearly straight; inner 



secondaries lengthened. . . . ALAUDID^E, 25. 



kkk. No crest ; nostrils exposed ; tarsus strictly " oscine." 



L Hind claw much elongated, twice as long as middle claw, 



with its toe much longer than middle toe and claw; 



bill very slender; longest secondary nearly equal to 



primaries in closed wing. . MOTACILLIDJE. 2<. 



II. Hind claw not specially elongated, not twice as long as 



middle claw ; inner secondaries not lengthened. 



m. Bill stout, compressed, notched, and abruptly hooked 



at tip; general color olivaceous, tail noi blotched 



with white or yellow. . . VIREOXID.*:, 31. 



mm. Bill various, notched or not, but little, if at all, 



hooked; colors often brilliant. SYLVICOLID.*:, 27. 



II. Clatnatore*. Outside of tarsus covered with a series of plates 



variously arranged, lapping entirely around in front and 



behind to meet in a groove on the inner side ; primaries 10. 



)i. First primary lengthened, often longest, always more than j 



length of the longest; bill broad, depressed, tapering to a 



point which is abruptly hooked; rictal bristles numerous; 



nostrils overhung but not concealed ; tail not tipped with 



yellow. .... TYRAXNID/E, 36. 



H. FAMILIES OF PICARI-E. 



I. Feet zygodactyle (two toes in front, two behind) by reversion 



of outer toe: (hallux wanting in Pi'coides.) 

 a. Tail scansorial, of 12 rigid, acuminate feathers, of which the 



outer pair are short and concealed ; bill stout and straight ; 



nasal tufts usually developed. . . . PICID.F,. 42. 

 aa. Tail not scansorial, of 8 to 10 long, soft feathers; bill de- 



curved ; no nasal tufts ..... CCCULIDJE, 41. 



II. Feet syndactyle, by cohesion of outer and middle toes; tibiae 



naked below; bill stout and straight, longer than head. 



Ill- Feet neither zygodactyle nor syndactyle; wings long and 

 pointed. 



