以X射線照射問荊（Equisetum arvense L.）之孢子各5秒、15秒、30秒或60秒後，利用穿透式電子顯微鏡觀察其孢子壁與原生質微細構造之變化。結果發現，問荊之外孢子對於X射線的抗力較對二乙胺有機溶劑的抗力大，而孢子壁的分子結構亦可藉由X射線照射顯現出來。由本研究可知，孢子壁各層次對於放射線及有機溶劑的抗性表現不同，故可藉此瞭解孢粉質的生物多聚體系統構造。

　　　　　Fresh spores of Equisetum arvense L. were irradiated for 5s, 15 5s. 30s or 60s, and examined with a transmission electron microscope. Alterations to the fine structure of the spore wall and the protoplasm are described. The exospore was more resistant to X-ray irradiation than to organic solvents, in particular diethylamine. The molecular structure of the spore wall was revealed by the X-ray effect. Resistance of the different layers of the sporomorphs to irradiation and organic solvents is important for understanding the complicated biopolymer system of the sporopollenin.