Page:The Harveian oration, 1873.djvu/32

 . 2.—Heart of Sheep. The right ventricle is laid open. The letter M indicates the moderator band. A probe has been passed between the chordae tendineae, passing from a musculus papillaris arising from the movable wall of the ventricle to the two main segments of the tricuspid valves and the outer wall of the ventricle.