The tertiary vascular bundles were regularly,concentrically and centrifugally arranged and partitioned with connective parenchyma whose ring numbers were the same as that of extra cambium.

• 三生维管束以离心方式排列成整齐的同心环状；由薄壁结合组织将其彼此分开；其圈数与额外形成层的圈数是一致的；随着根的个体发育而不断增加.