The left ventricle and the commencement of the aorta laid open. Mpm, Mpl, the papillary muscles. From their upper ends are seen the chordae tendinae proceeding to the edges of the flaps of the mitral valve. The opening into the uricle lies between tehse flaps. At the beginning of the aorta are seen ints three pouch-like semilunar valves.
Martin, H. Newell The Human Body: A Text-book of Anatomy, Physiology and Hygiene (New York: Henry Holt and Company, 1900) 168