Collateral or bicollateral vascular bundle, developmental pith and medullary ray are obvious.

髓发达，髓射线明显。

Ground meristem The central region of the apical meristem from which the ground tissues of pith, cortex, medullary rays, and mesophyll differentiate. In root meristem it is also called periblem.

端分生组织的中，髓、皮层、髓射线以这些基本组织均是由基本分生组织分化而成。根分生组织也称为皮层原。