![](/drem/stage22/labels2/S253L.gif)
![artifact space(s), basal plate of mesencephalon, cerebral aqueduct (mesocoele), exoccipital, head mesenchyme, oculomotor nucleus, osteogenic layer, rhombencoel (fourth ventricle), roof plate, subarachnoid space, sulcus limitans, surface ectoderm, tectum of mesencephalon, trochlear nucleus, vestibular area](/drem/stage22/Z0/S253N.jpg)
![](/drem/rulerbg.png)
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Boyd Embryo #H983 | Location: 22-1-1
Keywords: artifact space(s), basal plate of mesencephalon, cerebral aqueduct (mesocoele), exoccipital, head mesenchyme, oculomotor nucleus, osteogenic layer, rhombencoel (fourth ventricle), roof plate, subarachnoid space, sulcus limitans, surface ectoderm, tectum of mesencephalon, trochlear nucleus, vestibular area
Source: The Virtual Human Embryo.