The innermost layer of the cortex that forms a sheath around the vascular tissue of roots and some stems.
内皮层皮层的最内层，在根、茎的导管组织周围形成一道叶鞘（茎衣）
A network of extremely small blood vessels passing between the pia mater and the cerebral cortex.
大脑绒被从软膜和大脑皮层之间穿过的极细的小血管形成的网
Having a cortex or a similar specialized outer layer.
有皮的有皮的或具有相似的专门发育的外部覆盖的
