الفهرس 
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Abstract
At 0.8 cm CVRL stage, the optic pit was formed as a pair of shallow grooves on either side of the neural fold. At 1.5 cm CVRL stage, the optic vesicle was formed as a result of aggregation of neuroectodermal cells at lateral sides of the primitive fore-brain. At 2cm CVRL stage the vesicle became modified into a crescentic cup-like structure comprising an outer, thinner pigmented cell layer, and an inner, much thicker one separated by a narrow intraretinal residual space. The outer thinner layer was formed from a single layer of pigmented cells ”the pigmented retinal epithelium”, while the inner thicker layer ”the presumptive neural retina” was representing the bulk of the cellular elements of the optic cup. The ganglion cells were firstly differentiated at 6cm CVRL stage and were more prominent at 9 cm CVRL stage that separated from neuroblastic cells by the inner plexiform layer. The inner and outer limiting membranes of the neural retina were detected as early as 2cm CVRL. The apoptotic changes were visible among the ganglion cells more than the neuroblastic cells at 9cm CVRL stage. The inner nuclear layer was firstly observed at 30 cm CVRL stage associating with the first appearance of the retinal blood vessels in the nerve fiber layer. The inner nuclear layer became exhibited its full differentiation between 35 -40 cm CVRL stage and became separated from the outer nuclear layer by the outer plexiform layer. First appearance of the photoreceptor cell layer was observed at 47-55 cm CVRL stage, which became more prominent at 60 cm CVRL stage, consisting from rod and cone cells. At 74cm CVRL stage, the photoreceptor cells became differentiated into outer and inner segments which became more prominent at 98cm CVRL stage. All layers of the retina were completely differentiated at 80-115cm CVRL stage, comprising ten retinal layers. The differences in posterior and peripheral retinal thickness were observed during developmental stages. The mitotic activity was noticed throughout all developmental stages. At 3.5 cm CVRL stage, the optic nerve was inforced by blood vessels. The Bergmeister’s papilla was observed at 6cm CVRL stage as a mass of basophilic nuclei at the mouth of the optic disk that decreased in 9cm CVRL stage and became absent at