Lines = flow of inhalant water. VVV = flow of exhalant water.
After passing the leaflets, the current, now exhalant, is propelled by cilia forwards along the pallial groove to exit the gill-less anterior on the right of the animal. Faeces from the anus, and urogenital emissions of the nephridopores, located at the posterior right of the nuchal cavity, are conveyed to, and expelled from, the right anterior of the shell by cilia and the flow of exhalant water.
Concise
Part 1, SHELL FORMS: 02 Patella pellucida. Growth Stage 2 (GS2). July 2012. Littoral. North Yorkshire, England. © P. Lightfoot.
Part 2, BODY & ANATOMY: 03 Patella pellucida. Growth Stage 3 (GS3). 2009. Sublittoral, Farne Islands, Northumberland, England. © P.Lightfoot.
Part, 3 HABITS & ECOLOGY: 04 Patella pellucida. Length 4.6mm. Growth Stage 3 (GS3). September 2016. Yorkshire, England. © P.Lightfoot.