^ °'i 907^1 Cameron, Birds of Custer & Davenport Counties, Mont. 257 



the feathers of the neck standing on end, a pink inflated sac is disclosed. 

 At the same time the head is carried so low as almost to touch the ground, 

 so that the bird is transformed in appearance and, as observed through 

 binoculars at some distance, looks to be running backwards. He then 

 returns at full speed when another cock comes forward towards him, 

 both advancing slowly, with vibrating tails, to meet finally and stand 

 drumming their quills in a trance with tightly closed eyes. After perhaps 

 a minute one bird peeps at the other, and seeing him still enraptured, 

 resumes an upright graceful carriage, anon stealing gently away. His 

 companion is thus left foolishly posing at nothing, but presently he too 

 awakes, and departs from the arena in a normal manner. Meanwhile 

 the remaining cocks, one after another, take up the running till all have 

 participated, but the end of each figure seems to be the same. Two birds 

 squat flat on the ground with their beaks almost touching for about twenty 

 minutes, and when they do this they are out of the dances for that day. 

 As the grouse make their runs at intervals the play is spread over an hour 

 and a half, but when this was at its height the small open space, about 

 thirty yards in diameter, presented an indescribable scene. While three 

 or four of the metamorphosed cocks might be 'running,' the pairs already 

 formed would squat flat with outspread wings, and other cocks, facing 

 each other, would drum in ecstasy, oblivious to their surroundings. At 

 the same time an ardent suitor would now and again chase a hen across 

 the playground until she leaped high in the air, upon which the pursuer 

 would seem to forget her and make a 'run.' After watching for about 

 an hour the hens too made little runs but displayed no air sacs. All this 

 time the spectators of the dance, concealed by sage brush, kept up an 

 incessant coo, coo, coo, as if to applaud. The proceedings were quite 

 amicable throughout. I did not see the slightest inclination to fight on 

 the part of the performers: on the contrary, if two cocks collided, as some- 

 times happened, they would squat in apologetic fashion. After upwards 

 of an hour of running, posing and flopping, the dancers became exhausted, 

 and were constrained to pant painfully, a result not to be wondered at, 

 seeing that during the play period 90° in the shade was registered. The 

 dance appears to terminate by some bird, either a late starter or one more 

 vigorous than the rest, being unable to find a partner to respond to his 

 run. Having assured himself of this, he utters a disgusted clucking, and 

 all the grouse fly away at intervals as they complete their term of squatting. 



On April 29 and 30 I again watched the play which was still being energet- 

 ically carried on although the runs were, of course, fewer, the drumming 

 with the tail louder, and the crouching process more prominent and pro- 

 longed; whereas earlier in the month only two or three pairs squatted, 

 now seven couples nestled together as close as possible, and whenever a 

 disengaged bird approached, one of the pair rose to drive it away with the 

 regular chicken dance run. I concluded that these affectionate pairs 

 were birds mated for nesting although no act of pairing was witnessed by 



