突嘴型果点无木栓细胞结构,属初生类型;
Secondly, there was a little of collenchyma whose texture was tight in smooth type's endothecium of phellem;另外,光皮型杜仲在栓内层分布有较少的,质地紧密的石细胞群;
Configuration feature: For lofty deciduous leaf arbor, the bark of grown tree has the phellem layer that develop.形态特征:为高大的落叶乔木,成年树的树皮有发达的木栓层。