Skip Navigation
Stage 1 / 1 day Stage 2 / 2-3 days Stage 3-1 / 4 days Stage 3-2 / 4-5 days Stage 4 / 6 days Stage 5a-1 / 7 days Stage 5a-2 / 8 days Stage 5b / 9 days Stage 5c / 12 days Stage 6 / 13-17 days Stage 7 / 16-19 days Stage 8 / 23 days Stage 9 / 25 days Stage 10 / 28 days Stage 11 / 29 days Stage 12 / 30 days Stage 13 / 32 days Stage 14 / 33 days Stage 15 / 36 days Stage 16 / 39 days Stage 17 / 41 days Stage 18 / 44 days Stage 19 / 45-47 days Stage 20 / 49 days Stage 21 / 49-52 days Stage 22 / 52-55 days Stage 23 / 56 days
Atlas of Human Embryos Chapter   Figure

C-2 spinal ganglion, C-3 spinal ganglion, alar plate(s), anterior cerebral artery, attachment of optic stalk to diencephalon, auditory tube, basal plate, blood vessel(s), cartilage of branchial arch 2, chorda tympani nerve, choroid fissure, edge of tongue, external acoustic meatus, extraocular muscle, facial nerve (CN VII), floor plate, hypoglossal nerve (CN XII), hypophyseal stem remnant, inferior ganglion of glossopharyngeal nerve (CN IX), internal carotid artery, internal jugular vein, intraretinal space (optic vesicle cavity), mantle zone, marginal zone, maxillary nerve (CN V₂), middle cerebral artery, occipital lamina, ophthalmic nerve, optic chiasma, optic cup, optic part of retina, optic stalk, pallium, primitive pharynx, primitive tympanic cavity, roof of 3rd ventricle, roof plate, spinal accessory nerve (CN XI), striatal ridge, sulcus limitans, tela choroidea, third ventricle, vagus nerve (CN X)

A section through the C-3 spinal ganglion and the junction of the auditory tube (first pouch) with the primitive pharynx.

Observe:
1. The rostral end of the diencephalon where the optic stalk arises and courses to the optic cup.
2. The condensations representing the extraocular muscles dorsal to the optic cup.
3. The relation of the ophthalmic and maxillary nerves to the optic cup.
4. The edge of the tongue in the floor of the primitive pharynx.
5. The chorda tympani branch of the facial nerve passing between the external acoustic meatus and the primitive tympani cavity.


Keywords: C-2 spinal ganglion, C-3 spinal ganglion, alar plate(s), anterior cerebral artery, attachment of optic stalk to diencephalon, auditory tube, basal plate, blood vessel(s), cartilage of branchial arch 2, chorda tympani nerve, choroid fissure, edge of tongue, external acoustic meatus, extraocular muscle, facial nerve (CN VII), floor plate, hypoglossal nerve (CN XII), hypophyseal stem remnant, inferior ganglion of glossopharyngeal nerve (CN IX), internal carotid artery, internal jugular vein, intraretinal space (optic vesicle cavity), mantle zone, marginal zone, maxillary nerve (CN V₂), middle cerebral artery, occipital lamina, ophthalmic nerve, optic chiasma, optic cup, optic part of retina, optic stalk, pallium, primitive pharynx, primitive tympanic cavity, roof of 3rd ventricle, roof plate, spinal accessory nerve (CN XI), striatal ridge, sulcus limitans, tela choroidea, third ventricle, vagus nerve (CN X)

Source: Atlas of Human Embryos.