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Atlas of Human Embryos Chapter   Figure

alar plate(s), anterior cerebral plexus, basal plate, communication of C-1 spinal nerve and hypoglossal nerve (CN XII), cranial end of notochord, dorsal thalamus, extra-ocular premuscle mass for oculomotor (CN III) and trochlear (CN IV) nerves, floor plate, greater petrosal nerve, hypoglossal nerve (CN XII), hypothalamus, internal carotid artery, lateral rectus premuscle mass for abducens nerve (CN VI), mandibular nerve, maxillary nerve (CN V₂), neural canal, notochord, ophthalmic nerve, parachordal condensation, pharyngeal pouch 2, precardinal vein (internal jugular vein), primitive maxillary vein, primitive pharynx, roof plate, spinal accessory nerve (CN XI), sulcus dorsalis, sulcus limitans, sulcus medius, sulcus ventralis, tubotympanic recess (pharyngeal pouch 1), vagus nerve (CN X), ventral thalamus

A section through the cranial end of the notochord and edge of the primitive pharynx and internal carotid artery.

Observe:
1. The four plate areas of the spinal cord.
2. The anterior cerebral plexus and primitive maxillary vein that join with the primary head vein seen in Section 9.
3. The caudal continuation of the primary head vein as the precardinal vein.
4. The extraocular premuscle mass where cranial nerves III and IV terminate and the lateral rectus premuscle mass where cranial nerve VI terminates.
5. The communication between the C-1 spinal nerve and the hypoglossal nerve.


Keywords: alar plate(s), anterior cerebral plexus, basal plate, communication of C-1 spinal nerve and hypoglossal nerve (CN XII), cranial end of notochord, dorsal thalamus, extra-ocular premuscle mass for oculomotor (CN III) and trochlear (CN IV) nerves, floor plate, greater petrosal nerve, hypoglossal nerve (CN XII), hypothalamus, internal carotid artery, lateral rectus premuscle mass for abducens nerve (CN VI), mandibular nerve, maxillary nerve (CN V₂), neural canal, notochord, ophthalmic nerve, parachordal condensation, pharyngeal pouch 2, precardinal vein (internal jugular vein), primitive maxillary vein, primitive pharynx, roof plate, spinal accessory nerve (CN XI), sulcus dorsalis, sulcus limitans, sulcus medius, sulcus ventralis, tubotympanic recess (pharyngeal pouch 1), vagus nerve (CN X), ventral thalamus

Source: Atlas of Human Embryos.