STUDIES ON THE WARTY LAYER IN VESSEL ELEMENTS AND FIBRES OF MAIN CHINESE HARDWOOD BY ELECTRON MICROSCOPY Comparative Anatomical Studies on Vessel Elements of Chinese Ranunculaceae Spiral Thickenings of Vessel Elements in Magnoliaceae in China Comparative Anatomical Studies on the Vessel Elements of Eight Genera in Magnoliaceae Comparative Anatomical Studies on the Vessel Elements of Chinese Magnolia and Michelia Study of Vessel Elements in Pteris vittata Study on the Vessel Elements and Its Perforation Plate of Secondary Xylem in Ziziphus mauritiana Studies on the Vessel Elements of Secondary Xylem in Manilkara zapota Comparative Studies on Anatomical Structure of Roots in Three Citrus Seedling Rootstocks and Their Two Somatic Hybrids Comparative Investigation of Vessel Elements in the Secondary Xylem of Liriodendron Comparative Studies on Anatomical Structure of Roots in Three Citrus Seedling Rootstocks and Their Two Somatic Hybrids Study on the vessel elements and tylosis of secondary xylem in Averrhoa carambola