Action of Semilunar Valve
Section of the aorta, to show the action of the semilunar valve. A is intended to show the valves, represented by the dotted lines, lying near the arterial walls, represented by the continuous outer line. B (after Hunter) shows the arterial wall distended into three pouched (a), and drawn away from the valves, which are straightened into the form of an equilateral triangle, as represented by the dotted line.
Baker, W. Morrant & Harris, Vincent Dormer Kirkes' Hand-book of Physiology, 13th ed. (Philadelphia: P. Blakiston's Son & Co., 1892) 192