Search results
Results from the WOW.Com Content Network
The nictitating membrane of a masked lapwing as it closes over the left eye, originating from the medial canthus. The nictitating membrane (from Latin nictare, to blink) is a transparent or translucent third eyelid present in some animals that can be drawn across the eye from the medial canthus to protect and moisten it while maintaining vision.
The frog was named for the purple-blue colouration on the hidden portion of its hindlegs. [2] The species is mostly dark green, [3] with reddish-brown irises, and a mostly clear nictitating membrane, besides the darker dorsal margin. Adult males reach an estimated size of or under 66.6 mm (2.62 in).
Agalychnis callidryas, commonly known as the red-eyed tree frog or red-eyed leaf frog, ... Image of the nictitating membrane seen in red-eyed tree frogs.
It is loose, thus eye movements are not restricted by it. Only one species of primate, the Calabar angwantibo, is known to have a functioning nictitating membrane. [4] With ocular allergies, the lacrimal caruncle and plica semilunaris may be inflamed and pruritic (itchy) due to histamine release in the tissue and tear film.
Each eye has closable upper and lower lids and a nictitating membrane which provides further protection, especially when the frog is swimming. [84] Members of the aquatic family Pipidae have the eyes located at the top of the head, a position better suited for detecting prey in the water above. [ 83 ]
The Harderian gland is a gland found within the eye's orbit that occurs in tetrapods (reptiles, amphibians, birds and mammals) that possess a nictitating membrane. [1] The gland can be compound tubular or compound tubuloalveolar, and the fluid it secretes (mucous, serous or lipid) varies between different groups of animals.
There is also a third eyelid on each eye, the nictitating membrane. ... Their diets also consist of frogs, lizards, and bird's eggs and chicks. [44]
Birds, reptiles and sharks blink with a nictitating membrane from one side of the eye to the other. Blinking provides moisture to the eye by irrigation using tears and a lubricant the eyes secrete. The eyelid provides suction across the eye from the tear duct to the entire eyeball to keep it from drying out.