From Edward Curtis’ Field Notes:

“The sisiutlilahl makes his entrance with a club in his hand after striking the door with the weapon….The two hinged arms representing the body and heads of the double-headed snake sisiutl are at first folded together, extending straight back behind the man’s head, but they are now unfolded and spread out on both sides. The apparatus is manipulated by a man concealed behind the singers.” – Edward S. Curtis

Volume 10, The Kwakiutl, 1915. Plate facing page 214.