Fig. 4.—Human Heart. The right ventricle has its cavity exposed. The moderator band M is seen to pass up from the base of a musculus papillaris arising from the outer or movable wall of the ventricle into the neighbourhood of the conus arteriosus. Close to this, its upper end, a chorda tendinea arises by two roots, and passes up to the most posteriorly placed of the three cusps of the tricuspid valve.
