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"Having a sinuous pallial margin and consequent sinuous impression on the shell along the line of attachment of the mantle. Into the sinus thus formed the siphons, which are always developed in these bivalves, can more or less be withdrawn." —Whitney, 1889

Iphigenia Brasiliensis - Sinupalliate Right Valve

"Having a sinuous pallial margin and consequent sinuous impression on the shell along the line of attachment…