Girdle. Specimen from Orkney. February 2015. Leg. P. Lightfoot per J. Porter.
1: scalloped edge marks position of removed valves. 2: coloured bands faded after death and preservation in alcohol.
3: white mantle tissue forming thick girdle covered by coloured perinotum (dorsal cuticle).
4: coloured perinotum with widely spaced, very small spicules just visible as fine grains at this magnification of a cleaned surface.
5: strong, lateral, longitudinal muscle encircles the entire body passing under the outer margins of the valves (see also 50 Tonicella marmorea ).
6: lateral muscles connect the foot to the ends of the valves.

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