These demons are capable of concealing their eye colour with a sort of nictitating membrane which makes the eyes appear human.
22.
Some reptiles, mammals and birds have a translucent third eyelid that moves horizontally across the eye called the nictitating membrane.
23.
These sharks have only 1 dorsal fin, 6-7 gill slits, and no nictitating membrane on the eyes.
24.
Hexanchiform sharks have only one dorsal fin, either six or seven gill slits, and no nictitating membrane in the eyes.
25.
In some breeds of dogs, the nictitating membrane can be prone to prolapse, resulting in a condition called cherry eye.
26.
Lemurs also have a third eyelid known as a nictitating membrane, whereas most other primates have a lesser developed plica semilunaris.
27.
They appear to have a well-developed olfactory system, When the animal completely submerges, the nictitating membranes cover its eyes.
28.
In animals without eyelids, the role is played generally by some other membranes and nictitating membrane .-Dr . Rajarshi, India
29.
In the tear ducts, or the so-called " third eyelid " ( nictitating membrane ) or in the eyeball itself.
30.
Woodpeckers tighten their nictitating membrane a millisecond prior to their beak impacting the trunk of a tree to prevent shaking-induced retinal injury.
