The nictitating membrane is the transparent layer the covers the
outside of a frogs eye.
Frogs have a so-called Nictitating membrane, which they can
slide over their eyes for protection. They do this while jumping
and swimming.
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The membrane is. SOME problems with it are too.
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The nictitating membrane.
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depends on the species.
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A nictitating membrane The nictitating membrane is the THIRD
eyelid, the SECOND eyelid that you asked about is just that, the
eyelid, just like in humans