THE PRAIRIE SHARP-TAILED GROUSE. 105 



space occupied by the dancers is from 50 to 100 feet across, and as it is returned 

 to year after year, the grass is usually worn off, and the ground trampled down 

 hard and smooth. The 'dancing' is indulged in at any time of the morning or 

 evening in May, but it is usually at its height before sunrise. Its erotic char- 

 acter can hardly be questioned, but I can not fix its place or value in the 

 nuptial ceremonies. The fact that I have several times noticed the birds 

 join for a brief 'set-to' in the late fall, merely emphasizes its parallelism to 

 the drumming and strutting of the Ruffed Grouse, as well as the singing of 

 small birds. 



"The whole affair bears a close resemblance to the manoeuvring of the 

 European Ruff, and from this and other reasons I am inclined to suspect 

 the Sharp-tail of polygamy. When the birds are disturbed on the hill they 

 immediately take wing and scatter, uttering as they rise their ordinary 

 alarm note, a peculiar vibratory 'cack, cack, cack.' This is almost always 

 uttered simultaneously with the beating of the wings, and so rarely, except 

 under these circumstances, that at first I supposed it was caused by the 

 wings alone, but since then I have heard the sound both when the birds 

 were sailing and when they were on the ground, besides seeing them fly off 

 silently. They have also a call, a soft, clear whistle of three slurred notes, 

 E, A, D, and a sort of grunt of alarm, which is joined in by the pack as 

 they fly off. Their mode of flight is to flap and sail by turns every 40 or 

 50 yards, and so rapid and strong are they on the wing that I have seen 

 a chicken save itself by its swiftness from the first swoop of a Peregrine 

 Falcon, while another was seen to escape by flight from a Snowy Owl. 



"The nest of this subspecies is placed in the long rank grass, under some 

 tuft that will aid in its concealment, and is usually not far from a tract of 

 brush land or other cover. It is little more than a slight hollow in the 

 ground, arched over by the grass. The eggs, usually fourteen, but some- 

 times fifteen or sixteen, in number, are very small for the size of the bird. 

 Immediately before expulsion they are of a delicate bluish green; on being 

 laid they show a purplish, grape-like bloom; after a few days they become 

 deep chocolate brown, with a few dark spots. After a fortnight has trans- 

 pired they are usually of a dirty white. This change is partly due to 

 bleaching and also to the scratching they receive from the mother's bill 

 and feet. 



"Incubation lasts about twenty-one days. The young when first hatched 

 are covered with golden yellow down, and are spotted with black above. 

 This covering assists them materially in hiding when they squat in the 

 grass. At the age of six weeks they are fully feathered, and at two months 

 fully grown. Although still under guidance of the mother at this time, there 

 are usually not more than six or seven young ones left out of the original 

 average brood of fourteen, which shows the number of chicks which fall a 

 prey to their natural enemies, while many sets of eggs also are destroyed 

 by the fires which annually devastate the prairies. As the fall advances, 



