138 Birds of Colorado 



when hatched, are covered with do^vn and able to run 

 and fly almost at once. 



Key of the Families and Genera. 



A. Head completely feathered. 



a. Tarsus bare and not feathered (Odontophoridce). 



a^ Head without a true crest, tail shorter, about | of wing. 



Colinus, p. 138 

 b^ Head with a full, soft crest ; tail longer, about * of wing. 



Callipepla, p. 141, 



c^ Head with an upstanding club-^aped crest, distinct from 



crown -feathers. Lophortyx, p. 142. 



b. Tarsus always more or less feathered (Tetraonidce). 



a^ Tarsus feathered for half its length ; with shoulder rufis, 



Bonasa, p. 147. 



b^ Tarsus feathered to the bases of the toes at least, but toes 



not completely feathered. 



a- Tail long, about equal to the wing, highly graduated and 



attenuated. Centrocercus, p. 153. 



* b^ Tail long, about i of wing ; not attenuated, slightly 



rounded. Dendragapus, p. 145. 



c^ Tail short, less than | of wing. 



a^ Tail strongly graduated, middle tail-feathers projecting ; 



no tufts. Pediocaetes, p. 151. 



b' Tail moderately graduated, middle -tail-feathers not 



projecting ; neck tufts present. Tympanuchus, p. 150. 



c^ Tarsus and toes densely feathered throughout. 



Lagopus, p. 148. 



B. Head and neck naked ; tarsus not feathered {Meleagridce). 



Meleagris, p. 155. 



Family ODONTOPHORID^. 



Head fully feathered ; tarsus bare and without a spur ; 

 hind toe jointed above the level of the others ; plumage 

 never metallic. 



Genus COLINUS. 



Feathers of the crown lengthened and erectile, but hardly forming 

 a true crest ; tail of twelve feathers about f the length of wing. 



The genus is confined to North America, and goes as far south as 

 Yucatan. There are two species only in the United States ; the 



