【摘要】 对领春木(EupteleapleiospermumHook.f.etThoms.)次生木质导管穿孔板上穿孔中纹孔膜残留的观察表明,纹孔膜的残留非常丰富,类型多样,包括从接近具有完整的纹孔膜到基本完全消失的纹孔膜之间存在着连续的过渡类型。根据观察结果认为,领春木次生木质部中的导管可能代表了一种系统发育过程中的原始或过渡状态,因此领春木科也应该是一个比较原始的木本双子叶类群。更多还原

【Abstract】 The pit-membrane remnants in the perforation plate of the vessels in the secondary xylem of Euptelea pleiospermum were examined,which showed that there existed rich and diverse types of pit-membrane remnants including nearly complete pit membrane,and completely disappeared pit membrane and continuously transitional pit membranes.According to the results achieved in the examination,the authors of this paper hold that the vessels in the secondary xylem of Euptelea pleispermum may represent a primitive or transitional state in phylogenetical process and thus Euptelea pleiospermum should be a relatively primitive primitive woody dicotyledon.更多还原