104 A FIELD GUIDE .IN NATURE-STUDY 



II Upper parts brown but streaked or spotted, at 

 least tail and wings 



Bill slender; tail either cocked up or with 

 stiff, bristle-tipped feathers 

 X Seen on tree trunks, running up and 



down clinging to bark Brown Creeper 



XX Not with the foregoing habits 



Y No line over the eye House Wren 



YY With a line over the eye 



a Tail tipped with grayish white Bewick's Wren 



aa Tail not tipped with white 

 o Back streaked with white 



x Crown streaked Short-billed Marsh Wren 

 xx Crown not streaked Long-billed Marsh Wren 

 oo Back not streaked with white 



x Belly heavily barred Winter Wren 



xx Belly unbarred Carolina Wren 



OO Bill short, mostly stout; tail neither cocked 

 up nor with stiff bristly tip 

 X Birds nearly as large or larger than a 

 robin 



Y With conspicuous bristles around 

 base of bill; bill very small; mouth 

 very large, its gape an inch or two 

 a White spot on wing Nighthawk 



aa No white spot on wing . 



o Slightly smaller than robin Whippoorwill 



oo Considerably larger than a 

 robin; the song like that of 

 whippoorwill but with an 

 added syllable; song more 

 slowly given Chuck-will's- Widow 



YY No bristles around bill; bill large 

 and stout; henlike in form, rising 

 from ground with a loud whirr 

 a 10 in. long; throat and line over 



eye white or light Bobwhite 



aa 1 8 in. long or nearly so, no line 

 over eye 



o Breast and belly white, indis- 

 tinctly barred; sides plainly 

 barred Ruffled Grouse 



oo Breast, belly, and sides all 



evenly barred Prairie Chicken 



