Kúnúh-kanánu, Bear's Belly, is wrapped in a bear skin to be prepared for the ritual dance of the medicine fraternity.
There's more information about Bear's Belly and the story how he killed that bear right here: http://curtis.library.northwestern.edu/curtis/viewPage.cgi?id=nai.05.book.00000261&volume=5&showp=1&size=3
Reference photo again by Ed Curtis (1908): http://curtis.library.northwestern.edu/curtis/viewPage.cgi?showp=1&size=2&id=nai.05.port.00000004.p&volume=5
Drawn with Corel Photopaint and a tablet by Wacom.