68 BULLETIN 50, UNITED STATES NATIONAL MUSEUM 



tomium moderately concave, slightly inflexed. Wing moderately large, 

 with longest primaries exceeding longest secondaries by nearly one-third 

 the length of wing; fourth primary longest, but third and fifth nearly as 

 long, the first (outermost) intermediate between seventh and eighth. Tail 

 about two-thirds as long as wing or slightly more, moderately rounded 

 to truncate, the rectrices (20) broad, with broadly rounded to truncate 

 tips. Tarsus about one-fifth as long as wing, completely clothed (except 

 on heel) with dense, soft, hairlike feathers, these extending over greater 

 part of basal phalanx of middle toe on each side; middle toe decidedly 

 shorter than tarsus, the inner toe reaching to penultimate articulation of 

 middle toe, the outer toe very slightly longer; hallux slightly shorter 

 than basal phalanx of inner toe ; upper surface of toes with a continuous 

 single series of very distinct transverse scutella, on each side of which 

 is a single series of rather small, subquadrate scutella, edged with short, 

 more or less indistinct, marginal pectinations (these sometimes obsolete) ; 

 claws relatively short, slightly curved, and blunt. 



Plumage and coloration. — Plumage in general compact, the feathers 

 distinctly outlined, except on anal region, where soft, downy, and blended ; 

 feathers of crown but slightly elongated, forming, when erected, an in- 

 conspicuous crest ; no elongated feathers on sides of neck, but a moderate 

 sized inflatable air sac present in males. Adult males with upperparts 

 grayish or dusky, more or less vermiculated, the tail plain dusky with 

 or without a lighter gray terminal band, the underparts mostly plain sooty 

 grayish, variegated on sides and, especially, flanks with white; adult 

 females more barred and more brownish in general coloration. 



Range. — Coniferous forests of western North America, from high 

 mountains of California and Arizona to upper Yukon and Mackenzie 

 River Valleys. (One species.)''^ 



" There is wide diversity of opinion as to whether the forms of this genus are 

 all conspecific or are more properly to be treated as two species, one containing 

 the forms fuliginosus, sierrae, howardi, and sitkensis, and the second, obscurus and 

 richardsonii. The birds when studied in the museum certainly give a picture of 

 conspecificity throughout, but against this must be weighed the fact that the 

 people most conversant with these birds in life are convinced of the reality of two 

 speciiic groups. The characters by which they separate the two are as follows: 

 (1) The downy young are yellow below in the fuliginosus group, white in the 

 ohsciirus group; (2) the hooting sacs of the male in the breeding season are thick, 

 large, tuberculate, and deep yellow in color in fuliginosus; not thick or tuberculate 

 and are purplish in obscunis; (3) the hooting noise of the courting male is uttered 

 from the ground and is audible for less than a hundred yards in ohscurus, while 

 in f'tiliginosus it is given from high up in trees and carries audibly for several 

 miles; (4) in fuliginosus the tail of the adult male is rounded, the feathers also 

 rounded at the tip; while in ohscurus the tail of the adult male is nearly square, 

 the feathers terminally truncate. 



