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Where does fertilization usually occur in lamp shells?
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lamp shells
Lamp shells on the sea floor off the coast of Massachusetts.
In lamp shells (brachiopods), fertilization typically occurs outside the shell.1
While eggs and sperm are discharged from the body through funnel-shaped excretory organs known as nephridia, the union of these gametes takes place in the surrounding water. There are exceptions, however; in a few genera, the young develop internally within brood pouches formed by a fold of the mantle, which is a soft extension of the animal's body wall.1