Articulate shells are always composed of calcium cabonate. Hinge teeth are present in the ventral valve and sockets in the dorsal valve. The dorsal valve often has a septum or internal ridge down the middle. Muscle scars can be found from the opening and closing of the brachiopod.
These are some of the brachiopods found in the Ottawa Area.
These are some photos of brachiopods
found in the Ottawa area and its environs (Wilson 1956).