WOOD ANATOMY OF TREES AND SHRUBS FROM CHINA .6. MAGNOLIACEAE

The wood anatomy of five genera of Magnoliaceae (59 native species, 2 introduced species) of China is described. Although the wood anatomy o f this family is rather homogeneous, it is possible to identify most s pecimens to genus. Magnoliaceae wood from China is characterised by di ffuse-porosity, scalariform to opposite vessel wall pitting, scalarifo rm perforations with few bars or in some Magnolia species simple perfo rations, ground tissue fibres with distinctly to minutely bordered pit s, marginal parenchyma and heterocellular rays mostly with one margina l row of square/upright cells. Intervessel and vessel-parenchyma pits are almost exclusively opposite in the Liriodendroideae; they are almo st exclusively scalariform in the Magnolioideae, except for magnolia s ection Rhytidospermum in which pits are predominantly opposite. Althou gh the wood anatomical characters more or less overlap between Magnoli a and Manglietia, these genera are wood anatomically distinguishable. Wood anatomy is similar in the evergreen species of Magnolia and Miche lia. Kmeria is the only genus in which crystals were observed. Taxa fr om the tropics to subtropics tend to have longer and wider vessel elem ents, and a lower vessel frequency than those from temperature provena nces; oil cells in rays mostly occur in the taxa from tropical and sub tropical provenances. Simple perforation plates are mostly present in the temperate taxa. Counter to trends for the dicotyledons at large, h elical thickenings are more common in tropical species than in tempera te species, and, when present, are usually not distinct in deciduous s pecies.