Frances Densmore recording Mountain Chief. Post here when you come across this iconic image.

http://upload.wikimedia.org/wikipedia/commons/thumb/1/1b/Frances_Densmore_recording_Mountain_Chief2.jpg/481px-Frances_Densmore_recording_Mountain_Chief2.jpg

It is on the cover of Indian Blues:American Indians and the Politics of Music, 1879-1934, by John W. Troutman, as well as being in the interior, where we are informed that the original caption was "Piegan Indian, Mountain Chief, having his voice recorded by ethnologist Frances Densmore."

It is on p. 39 of Marybeth Hamilton's In Search of the Blues, where it is captioned
The earliest known photograph of a Graphophone in use. Frances Densmore records Blackfoot leader Mountain Chief.

Wikipedia description sez:

English: Part of a series of pictures depicting Frances Densmore at the Smithsonian Institution in 1916 during a recording session with Blackfoot chief Mountain Chief for the Bureau of American Ethnology.

Library of Congress caption: "Piegan Indian, Mountain Chief, listening to recording with ethnologist Frances Densmore, 2/9/1916."
National Geographic caption: "This 1916 image of Frances Densmore and Blackfoot leader Mountain Chief listening to a cylinder recording has become a symbol of the early songcatcher era."

And links to Library of Congress here:
http://loc.gov/pictures/resource/npcc.20061/
where the caption is
Blackfoot Chief, Mountain Chief making phonographic record at Smithsonian, 2/9/1916

That's all I got for now.

*waits for Tim E*