The Foot Shell

THE FOOT SHELL Genus PEDUM, Brug.

Shell wedge-shaped, thin, nearly smooth, flattened, slightly curved ; right valve convex and deeply notched for passage of the byssus. A single species is known.

406 The Thorny Oysters The Thorny-oyster Foot Shell (P. Spondyloideum, Gmel.) has an outline somewhat suggesting the human foot. The animal between these flat valves must be very thin. It was first de

scribed as an oyster, and it long enjoyed a reputation for rarity. It is found most abundantly in the Red Sea where it is partially buried in coral reefs. Colour, brownish red in indistinct con centric bands on a paler ground. Length, 3 inches.

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