The corneal and palpebral sides of nictitating membrane (NM) consisted of a multi-layer flat epithelium. Belt-like hyaline cartilage present in the middle of the membrane The membrane has two parts; they are palpebral part which takes place on the upper side of the hyaline cartilage and corneal part which faces the cornea. When corneal and palpebral parts of the membrane are compared many differences are seen in the tightly structured and dense irregular connective tissue The membrane shows wavy appearance in the medial eye angle. In the palpebral surface; skeletal muscle bundles which are surrounded by dens irregular connective tissue run both longitudinally and vertically. Fat cells are seen groups or in disperse in the same side in addition to belt-shaped serous and mucous glands. Except skeletal muscle, lymph follicles were seen additionally in the corneal side when you compare it with the palpebral side.