THE MOUNTAINS 



365 



But a toiu'li 1)rolve the spell of her astonishing stillness, 

 and she fluttered oli' a few yards only to hecome motionless 

 again. Herein lies the secret of the invisible cloak which 

 these birds wear. It is not alone their faith in it that counts. 

 All ground inhabiting birds exhibit this confidence in the 





Ptarmigan on Nest 



protective value of the dull-tinted costumes to a greater or 

 less degree. In the gallinaceous birds it is most highly de- 

 veloped, but none, in my experience, equals the Ptarmigan. 

 The mottled male, with more or less white and black in his 

 plumage, might be thought a rather conspicuously marked 

 bird, but as long as he holds his rigid, statuesque pose, he is 

 simply a lichen-covered rock. Doubtless we passed within 

 a few feet of numl)ers of them and were none the wiser. 



The data obtained on this, our first day's outing, was 

 sufficient to insuic the successful accomplishment of the ob- 

 ject of our expedition. The haunting thought of failure was 



