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 view than if it were unextended. It is common in nature and in fiction.

In nature

In nature, eyestalks are sometimes called tentacles, and may have olfactory organs and/or eyes at the end. Examples include snails, the trilobite superfamily Asaphoidea, and fly family Diopsidae. The crustacean family Polychelidae have eyestalks but no eye.

In fiction

A beholder is a fictional character that sports numerous vertical eyestalks. Many Dalek variants have a horizontal eyestalk.

Tripods from Star Wars have eyestalks.

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