![](/drem/stage19/labels2/S98L.gif)
![alar plate of myelencephalon, cerebral aqueduct (mesocoele), isthmus of rhombencephalon, myelencephalon, rhombencoel (fourth ventricle), roof of rhombencoel (fourth ventricle), roof plate, subarachnoid space, trochlear nerve (CN IV)](/drem/stage19/Z0/S98N.jpg)
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Carnegie Embryo #9325 | Location: 3-4-2
Keywords: alar plate of myelencephalon, cerebral aqueduct (mesocoele), isthmus of rhombencephalon, myelencephalon, rhombencoel (fourth ventricle), roof of rhombencoel (fourth ventricle), roof plate, subarachnoid space, trochlear nerve (CN IV)
Source: The Virtual Human Embryo.