case cupboard furniture grip handle holdfast locker shank aluminium box handhold hold holder matal shine silver abstract algae background blue brown floats green haptera kelp lamina littoral marine nature ocean planktonic pools rock saavem sea sorus spore stipe texture thallus tidal water weed accumulations attached clinging coastline color colour covered ebb-and-flood ebb-and-flow filamentous holdfasts layers levels light low-tide pounding rocks rocky rough seashore seaside seaweed shadows shapes shore shoreline slimy slippery spray sticking stones stony stuck sunlight sunshine surf surge surging tide tides velvety waves wet