320 Birds of Colorado 



of the next. Tail of twelve feathers. Tarsus scutellated 

 ia front, the sides covered with two long undivided plates 

 forming a sharp ridge behind. One complete moult 

 in the year in the fall after the breeding season, but 

 frequently a partial change of colour in spring, due 

 to the wearing away and falling ofE of the worn 

 feather-tips. 



This family comprises the birds generally known as 

 Finches, Sparrows, Buntings and Grosbeaks, and is 

 spread all over the world, except in the Australasian 

 region. It is the largest of all North American bird 

 families, comprising about one seventh of the bird 

 population. 



Key of the Genera. 



A. Tail distinctly shorter than the wing, 

 a. Tail less than -7 of the wing. 



a^ Bill very large, culmen about equal to tarsus; rami of 

 mandible very short, only about 1 of gonys. 



Hesperiphona, p. 325. 

 b^ Bill with the tips of the mandibles crossed. Loxia, p. 333. 

 c* Bill small or moderate and normal. 



a^ Wings long and pointed ; difference between the 

 primaries and secondaries distinctly exceeding the 

 tarsus, 

 a* Nostrils concealed by forwardly growing bristles, 

 a* Tarsus shorter than the middle toe and claw, 

 a® Bill shorter and less acute ; plumage largely 

 yellow, not streaky. Astragalinus, p. 342. 



b' BiU longer and more acute ; plumage streaky 

 above and below. Spinus, p. 346. 



b* Tarsus longer than the middle toe and claw. 



a^ Upper and lower mandibles about equally deep ; 

 plumage with a good deal of pink. 



Leucosticte, p. 335. 

 b* Lower mandible distinctly deeper than the upper ; 

 no red in the plumage. Plectrophenax, p. 349. 

 b* Nostrils exposed. 



a* Plumage without pink ; claw of hind toe more or 

 less elongated and straight. Rhynchophanes, p.353. 



