350 BULLETIN- 50, UNITED STATES NATIONAL MUSEUM. 



Medium sized, rather small, or large Fringillidse with short, rounded 

 wing, rather long (nearly equal to or longer than wing), rounded or 

 double-rounded tail, and conspicuously streaked brownish plumage 

 (unstreaked below only in adult of M. georgiana). 



Bill variable in proportionate length and depth, but exposed culmen 

 ne^'er much more than half as long as tarsus and basal depth never less 

 than two-thirds the length of gonys nor more than length of the latter; 

 culmen gently convex for most of its extent, straight or faintly 

 depressed in middle or post-median portion; gonys straight or faintly 

 convex, nearly or quite equal to length of maxilla from nostril; max- 

 illary tomium with subterminal notch obsolete or wanting, very faintly 

 concave anteriorly and convex posteriorly, the slightly deflected basal 

 portion nearly or quite concealed by rictal feathers; mandibular tom- 

 ium straight to the subbasal angle. Nostril small, nearly circular, 

 partly concealed by bristly plumelets. Wing short (about two and 

 two-thirds to barely more than three times as long as tarsus), rounded 

 (eighth to fifth primaries longest, ninth shorter than fourth); prima- 

 ries exceeding secondaries by much less than length of tarsus (usually 

 by not more than length of exposed culmen). Tail equal to or slightly 

 longer than wing {cinerea), decidedly shorter than wing {lincolni) or 

 intermediate, the rectrices rather narrow, obtusely rounded at tips 

 (almost acuminate in georgiana), less than half overlaid by upper 

 coverts. Tarsus about equal to middle toe with claw or a little longer, 

 its scutella fairlj" distinct; lateral claws not reaching to base of middle 

 claw; hallux about equal to inner toe, its claw nearlj^ as long as the 

 digit. 



Coloration. — Above grayish, brownish, olive, or rusty, more or less 

 distinctlj' streaked, especially on the back, with darker; top of head 

 brownish, streaked with darker, and divided medially by a more or 

 less distinct grayish stripe, or else chestnut becoming black on forehead; 

 wings and tail brownish (usually more or less rusty) the former without 

 distinct light-colored bands; ear-coverts and superciliary stripe gray- 

 ish, separated by a brownish or dusky postocular streak; a whitish, 

 light grayish, or buffy malar stripe, bordered below by a more or less 

 distinct brown or dusky streak alongside of throat; lower parts mainly 

 whitish, the chest and sides usually streaked with rusty, brown, or 

 dusky. Young similar to adults, but markings less sharply defined 

 and colors more blended. 



The type-species of this genus is a bird of verj' extensive geographic 

 range, breeding throughout the temperate parts of the North American 

 continent, including the plateau of Mexico. No other bird of the 

 Nearctic Region has proven so sensitive to influences of physical 

 environment, and as a result of this plasticity of organization it has 

 become divided into a large number of geographic forms, some of 

 extensive others of very circumscribed range, the area of distribution 



