. Human embryology and morphology. Embryology, Human; Morphology. 178 HUMAN EMBRYOLOGY AND MORPHOLOGY. being pushed within the other. It is invaginated by the lens-bud in the same manner as a schoolboy's fist indents a punctured india-rubber ball. The invaginated vesicle is known as the optic cup. The invagination of the vesicle, which takes place in . chor. fis. f0n Monro cerebr. vesicle / /_. 3rd ventricle Olfact lamina term choroid, dep. optic recess pituitary r right op. ves. I turned down Fig. 145.—Diagram showing the condition of the Optic Stalk and Vesicle at the commencement of the 2nd
. Human embryology and morphology. Embryology, Human; Morphology. 178 HUMAN EMBRYOLOGY AND MORPHOLOGY. being pushed within the other. It is invaginated by the lens-bud in the same manner as a schoolboy's fist indents a punctured india-rubber ball. The invaginated vesicle is known as the optic cup. The invagination of the vesicle, which takes place in . chor. fis. f0n Monro cerebr. vesicle / /_. 3rd ventricle Olfact lamina term choroid, dep. optic recess pituitary r right op. ves. I turned down Fig. 145.—Diagram showing the condition of the Optic Stalk and Vesicle at the commencement of the 2nd month. (After His.) an oblique manner—the pressure being applied from below and behind, leads to the closure not only of the cavity of the vesicle, but also to that of the distal half of the stalk (optic nerve). The mesoblast, surrounding the lens, grows into the invagination and afterwards forms the vitreous humour. The artery, which is folded in with the mesoblast, becomes afterwards the central artery of the retina. Hence the point at which the central artery enters the optic nerve marks the upper limit of the invagination of the optic stalk. By the fourth week the optic vesicle no longer communicates with the cavity of the fore-brain but the recessus opticus, in the floor of the third ventricle, above the chiasma, marks the point at which it entered (Fig. 145). The optic fibres, developed as processes of the neuroblasts of the invaginated layer, grow into the brain from the retina along the optic stalk. They thus form the greater number of the fibres in the optic nerve. The optic fibres also form the chiasma in the floor of the third ventricle and the optic tracts on the wall of the fore-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Keith, Arthur, Sir, 1866-1955. London : E. Arnold
Size: 1692px × 1477px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectembryol, bookyear1902
