Abstract: A membrane for a mount having hydraulic damping action has a peripheral bead and opposite surfaces extending inwardly therefrom. A nonrectilinear cut through the opposite surfaces of the membrane from at least proximate the bead of the membrane delimits at least one tongue from the membrane which projects either centrally of the membrane or toward a thinner portion of the membrane. The mount for the membrane has working and equalizing spaces filled with an hydraulic fluid and arranged to vary in volume in response to relative movement between pedestal and mounting bracket portions of the mount. A throttle opening between the working and equalizing spaces throttles fluid flow therebetween in response to the pressure differential therebetween from the volume variation for hydraulic damping.