Eyelids definition of Eyelids in the Free Online Encyclopedia.

Eyelids

skin folds around the eyes in vertebrate animals and man. Eyelids serve to protect the eyeball from external injury, to moisten it with lachrymal fluid, and to remove foreign bodies from the eye. The majority of animals have paired (upper and lower), movable eyelids. In a number of sharks, amphibians, reptiles, birds, and some mammals, there is also a third movable eyelid—the nictitating membrane. In most mammals the third eyelid lacks musculature and is therefore immovable; in primates and in man it is reduced and forms a semilunar fold in the inner corner of the eye.

Eyelids in man consist of upper and lower movable skin folds that cover the eyeball when closed and circumscribe the eye aperture. The boundary of the upper lid is the recess between the orbit and the eyeball; the lower lid is separated from the cheek by a poorly defined furrow. The eyelids consist of skin, subcutaneous tissue, a muscle layer, a cartilaginous plate, and the conjunctiva. The skin of the eyelids is thin and turns into conjunctiva along the edges, where the eyelashes grow and the openings of the glands are located. The blood vessel network of the eyelids is well developed; sensory innervation is effected by branches of the trigeminal nerve; motor innervation is by the facial nerve.

Of greatest anthropological interest is the upper lid, the skin of which can form various types of folds—superior (suprapalpebral), median (palpebral), and inferior (tarsal). The last type of fold is more developed in the outer part of the eye and is manifested more strongly with age. Also distinguished is the Mongolian fold (epicanthic), which partially covers the lacrimal caruncle and is usually a continuation of the palpebral fold. The epicanthic fold is especially widespread among representatives of the Mongoloid race (up to 60 percent or more, especially frequent in women and children); it is absent among Caucasoids and Negroids (except for Bushmen).

REFERENCES

Roginskii, Ia. Ia., and M. G. Levin. Antropologiia, 2nd ed. Moscow, 1963.

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No references found	Send me word by telegraph whether you would like Truffles again, or whether you would prefer something simpler and lighter--say that incomparable French dish, Pig's Eyelids and Tamarinds. Law and the Lady by Collins, Wilkie View in context The East End of London, I read, or some one says; and first of all, under my eyelids, leap the visions of the shining pubs, and in my ears echo the calls for "two of bitter" and "three of Scotch. John Barleycorn by London, Jack View in context In bed, she projected against her closed eyelids the few rich scenes of her mother that her child-memory retained. The Valley of the Moon by London, Jack View in context	eye-house eyeball eyeball assay eyeball driven eyeball hang time eyeball potential eyeball search eyeballs eyebar eyebolt eyebrow eyebrow dormer eyebrow eave eyebrow lintel eyebrow monitor eyebrow window eyeglass Eyeglasses Eyeglasses, Polarized eyelash Eyelashes eyelet eyeleting eyelid eyelid dormer Eyelids eyelights Eyepiece Eyepiece Camera Eyepiece Prism eyepoint eyespot eyestalk Eyestrain eyetooth eyewash Eyjafjörður Eykman formula Eylau Eyre Eyre Peninsula Eyre, Edward John Eyre, Lake Eyre, Sir James Eyre, Wilson eyrie Eyring equation Eyring formula Eyring molecular system Eyring theory Eysenck	eyelid drooping eyelid drooping eyelid drooping eyelid eversion eyelid eversion eyelid eversion eyelid inflammation eyelid inflammation eyelid inflammation eyelid inversion eyelid inversion eyelid inversion eyelid limbus eyelid limbus eyelid limbus eyelid snapping eyelid snapping eyelid snapping eyelid speculum eyelid speculum eyelid speculum Eyelid twitch Eyelid twitch Eyelid twitch Eyelid twitches Eyelid twitches Eyelid twitches Eyelid twitching Eyelid twitching Eyelid twitching Eyelids eyelift eyelift eyelights eyelike eyeliner Eyeliner Sign eyeliners EYEM Eyemouth Herring Queen Eyemouth International Sailing Craft Association Eyen Eyeneer Folk/Bluegrass Archives EYEO Eyeology Eyeology Eyeore EYEOY EYEP eyepatch Eyepatches eyepiece eyepiece eyepiece Eyepiece Camera Eyepiece Focal Length Eyepiece lens Eyepiece lens Eyepiece lens

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Send me word by telegraph whether you would like Truffles again, or whether you would prefer something simpler and lighter--say that incomparable French dish, Pig's Eyelids and Tamarinds.

Law and the Lady by Collins, Wilkie View in context

The East End of London, I read, or some one says; and first of all, under my eyelids, leap the visions of the shining pubs, and in my ears echo the calls for "two of bitter" and "three of Scotch.

John Barleycorn by London, Jack View in context

In bed, she projected against her closed eyelids the few rich scenes of her mother that her child-memory retained.

The Valley of the Moon by London, Jack View in context