Eyestalk

In anatomy, an eyestalk (sometimes spelled as eye stalk or known as an ommatophore) is a protrusion that extends the eye away from the body, giving the eye a better field of vision. It is a common feature in nature and frequently appears in fiction.

In nature, eyestalks are sometimes called "tentacles", and may also have olfactory organs at their ends; examples of creatures with olfactory eyestalks include snails, the trilobite superfamily Asaphida, and the fly family Diopsidae. In slugs and snails, these tentacles will regrow if severely damaged, and in some species, are rectractable. The tentacles of aquatic snails do not regrow.

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