The eye develops from three elements: (i) Optic cup derived from prosencephalon, (ii) Lens vesicle derived from surface ectoderm, and (iii) Mesoderm surrounding the optic cup. Development of various parts of eyeball. Retina: It develops from posterior part of optic cup. Outer layer of optic cup forms pigment layer of retina; while rest of the layers are derived from inner layer of the optic cup. Lens: the lens develops from lens vesicle. Sclera choroid: The mesoderm around optic cup differentiates into inner vascular layer that forms choroid and outer fibrous layer that forms sclera. Cornea: Outer stratified squamous non keratinized epithelium of cornea develops from surface ectoderm; while other layers of cornea develop from underlying mesoderm. Ciliary body: Mesoderm around anterior part of optic cup forms ciliary muscles and connective tissue of ciliary body. Outer layer of optic cup forms pigment epithelium and inner layer of optic cup forms nonpigmented layer of epithelium of ciliary body. Iris: Anterior extension of two layers of optic cup forms the epithelium of iris. These epithelial cells of the iris also give rise to muscles of iris (sphincter papillae and dilator papillae) Vascular connective tissue of iris develops from mesoderm anterior to optic cup. The ear is divided into external middle and internal ear. External ear develops from first pharyngeal groove and middle ear develops from first pharyngeal pouch as described in pharyngeal apparatus. Internal ear develops from otic vesicle, which is derived from surface ectoderm on either side of myelencephalon.