The tentacles widely diverge from their bases near the midline of the head.
When translucent, the muzzle may reveal dorsally the oral tube (1) leading from the mouth to the buccal mass, and the oesophagus (2) passing from it towards the stomach. On weakly pigmented, translucent specimens, the dumbbell-shaped, dorsal part of the nerve ring with two cerebral ganglia (3) may be visible. The ring encircles the oesophagus. It and its ganglia that innervate organs on the head are the nearest approximation in gastropods to a centralised brain, but other ganglia distributed on nerve cords around the body innervate other organs.
Shell height 3.5 mm. Salting on tidal River Dee, Flintshire, Wales. December 2018.

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