Chambre à joues
A chambre à joues ('joue' is French for 'cheek') is a type of hand-camera popular around the beginning of the 20th century. The camera has a bellows but no base-board. Instead, there is a panel on each side of the bellows, usually of wood, hinged from the rear body and inserted behind the lens board to act as a strut. The type was largely superceded by cameras with metal struts.
Camera-wiki.org has few examples (see the Shew Xit).