nictitating membrane

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nictitating membrane

(in reptiles, birds, and some mammals) a thin fold of skin beneath the eyelid that can be drawn across the eye

Nictitating Membrane

 

a third eyelid, located in the inner corner of the eye in some Euselachiae (fishes) and the majority of terrestrial vertebrates. The nictitating membrane is formed from a fold of the conjunctiva and is located behind the upper and lower eyelids. In terrestrial vertebrates, a transparent nictitating membrane periodically covers the cornea to clean and moisten it. Nictitating membranes are most highly developed in reptiles and birds. Among mammals, a third eyelid is absent in Echidna and Cetacea; apes and humans have rudimentary nictitating membranes in the form of semilunar folds.

nictitating membrane

[′nik·ə‚tād·iŋ ′mem‚brān]
(vertebrate zoology)
A membrane of the inner angle of the eye or below the eyelid in many vertebrates, and capable of extending over the eyeball.
References in periodicals archive ?
Dr Jamil Ahmed said that the conjunctivitis is an inflammation or infection of the conjunctiva; a thin, transparent layer covering the surface of the inner eyelid and the front of the eye and it affects people of all ages.
Create a more dramatic effect by using the same pencil to draw a line along the inner eyelid.
It is alright to use these colours with a slight shimmer, even if you are using it on both the inner eyelids, as it helps to bring light to that area.
In summary, external ophthalmomyiasis should be kept in mind in the differential diagnosis of patients presenting with conjunctivitis and a thorough slit-lamp examination including the inner eyelids should be conducted to ensure the diagnosis is not overlooked.