GREATER PRAIRIE CHICKEN" 255 



the toes is " honey yellow," the undersurface " mustard yellow," and 

 the nails " flesh color." 



The young of the sharp-tailed grouse is similar to that of the 

 prairie chicken, but with the following minor differences : The yellow 

 of the unclerparts, not so deep or so bright as in the prairie-chicken 

 young. Upper parts with much less black, especially in the region 

 of the back and rump. The brown of the rump is a paler shade. 

 The black on the upper mandible extends down only one-half the dis- 

 tance of the length of the bill. When the young of the prairie 

 chicken and sharp-tailed grouse are compared with young of the 

 ruffed grouse, they are seen to be much yellower and much less 

 reddish brown, so characteristic of the day-old ruffed grouse. 



The average weight of 17 young prairie chickens that hatched in 

 a nest near Bancroft, Portage County, Wis., was 15.9 grams. The 

 average weight of the eggs 2 days before hatching was 19.4 grams. 



[Author's note : As with all young grouse, the wings and scapu- 

 lars begin to grow soon after the chick is hatched, and juvenal plum- 

 age is rapidly acquired, long before the young bird attains its growth. 

 In this plumage the crown is " hazel," spotted with black ; the feath- 

 ers of the back, scapulars, tertials, and wing coverts are boldly pat- 

 terned with " ochraceous-tawny," black, and " snuff brown," many 

 feathers, especially the scapulars, having broad white shaft streaks 

 spreading out into a white tip ; the primaries are spotted with pale 

 buff on the outer web; the pointed tail feathers are barred or pat- 

 terned with the colors of the back; the chin is white, and the under- 

 pays are dull white, washed with buff and spotted with dusky on 

 the breast and flanks. 



Before the young bird is fully grown, in July, the postjuvenal 

 molt begins with the primaries. This is a complete molt, except that 

 the outer pairs of juvenal primaries are retained for a whole year. 

 Otherwise the first winter plumage is practically adult. Adults have 

 a partial prenuptial molt, about the head, in March and April, and 

 a complete postnuptial molt in August and September.] 



In addition to the normal plumages of the prairie chicken there 

 are unusual types that have attracted the attention of sportsmen and 

 ornithologists. In certain individuals of the prairie chicken there 

 is a prevalence of rufous or reddish brown, which is due to an excess 

 of red pigment in the feathers, a condition known as erythrism. The 

 red phase of the plumage is a common occurrence among ruffed 

 grouse, but as yet it has been noted in comparatively few cases of 

 pinnated grouse. The following cases, which have come to my atten- 

 tion, are of interest : 



George N. Lawrence (1889) described a specimen in which all of 

 the light markings were tinged with light, bright rufous and the 



