406 CENTEOCERCUS UEOPHASIANUS, SAGE COCK. 



Some of those babits of the Sage Cock which are peculiar to the pair- 

 ing season were described by one of the earlier writers, doubtless with 

 substantial accuracy, and are quoted in the Fauna Boreali-Americana. 

 "They pair in March and April. Suiall eminences on the banks of 

 streams are the places usually selected for celebrating the weddings, 

 the time generally about sunrise. The wings of the male are lowered, 

 buzzing on the ground; the tail, spivad like a fan, somewhat erect; the 

 bare, yellow oesophagus inflated to a prodigious size — fully half as large 

 as his body, and, from its soft, membranous substance, being well con- 

 tra st<Ml with the scale-like feathers below it on the breast, and the tlexi- 

 ble, silky feathers ou the neck, which on these occasions stand erect. 

 In this grotesque form he displays, in the presence of his intended mate, 

 a variety of attitudes. His love-song is a confused, prating, but not 

 otfeusively disagreeable, tone — something that we can imitate, but have 

 difMculty iu expressing — hnrr-Jmrr-hurr-r-r r-lioo, ending in a deep, 

 hollow tone, not uulike the sound produced by blowing into a large 

 reed." 



Even those who are familiar with the appearance of the "drums" of 

 the common Pinnated Grouse when fully inflated, may fail, without 

 actual ins])ection, to form a fair idea of the enormous yellow air-sacs of 

 the Sage Cock in their condition of greatest distension. Instead of 

 being regularly hemispherical, like half a small orange, they are im- 

 meuse, bulging masses of irregular contour, seeming to meet in front, 

 and singularly distorting the figure of the bird — surmounted with a 

 Iringe of filaments depending from the mass of erect white feathers, and 

 ending below iu a solid set of white scaly plumes. Perhaps no bird of 

 our country presents a more remarkable asjjcct than the Sage Cock 

 under the circumstances just noted ; while at all times his presence and 

 bearing are sufficiently striking. The mode of flight is most like that 

 of the Shari>-tailed Grouse — indeed, what resemblances the Sage Cock 

 bears to any other of our birds, are closest, in all respects, with this 

 si)ecies. There is the same complete spread of the wing, when the ends 

 of the outer quills show spaces between them — the same heavy yet 

 swift and steady course, accomplished with an alternation of a few en- 

 ergetic strokes, and a period of sailing with stitfly motionless wings, 

 until the impulse is spent. A point in which the Sage Grouse differs 

 Irom the Sharp-tailed, if not also from every other one of our Grouse, is 

 that it never takes to the trees, its exclusively terrestrial habits being, 

 indeed, a necessity arising in the nature of the country it inhabits. 



The egg of the Sage Fowl may be recognized at a glance by its size 

 and elongated shape ; it is comparatively narrower and more pointed 

 than that of any other Grouse of this country, and our specimens, 

 selected from a great number in the Smithsonian collection, measure, 

 respectively, 2.25 by 1.50; 2.10 by l.GO; 2.10 by 1.50; 2.05 by 1.50. The 

 sbell first forms pale grayisli-wliite, with a faint greenish shade, and 

 subsequently becomes a grayish or greenish-drab by acquiring more or 

 less of a brown tint ; this is spotted with chocolate-brown, mostly iu 

 si^ecks and minute dots, pretty evenly and rather thickly distributed, 

 sometimes very sparsely so nuirked, and occasionally with larger spots 

 (size of a split pea) tending to a circular shape, with sharp edges. The 

 same circuhirity may be observed in the case of the smaller markings. 



An interesting law affecting egg-coloration may be deduced from 

 examination of eggs which, like those of all our Grouse and many other 

 birds, are colorless, or of uniform color at first, yet variously marked 

 wheu laid. In such cases, probably without exception, the markings 



