23 Steromphala cineraria. Menai Strait, Wales. February 2014.

23 Steromphala cineraria. Menai Strait, Wales. February 2014.

Whitish sole compressed on glass with tawny, raised, direct (= forward flow) compression waves. Ditaxic (= each half either side of median furrow moves out of phase with other). Snail turns by different rates of wave flow on either side. Multiple transverse creases.