3: muscle bundles demarcated by gaps.

Turquoise arrows:
Cilia on pallial gills (1) create local inhalent respiratory water currents from adjacent shell-rim onto gills, and exhalent current below gills back to shell-rim (Yonge & Thompson, 1976).

Thin blue arrows:
Route of cilia-transport of faecal matter from the anus in nuchal cavity (2) to accumulate at middle of right side (dotted arrows = route concealed by foot).

Thick blue arrows:
Water current from exterior into nuchal cavity and thence, carrying excreta and sperm/ova. They and accumulated faeces expelled from middle of right side by periodic sharp contraction of pedal-retractor muscle clamping shell down and forcefully flushing them out with water. (Fretter & Graham, 1994).

OTHER SPECIES ALBUMS
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