Abstract: 99 wood species of Gymnospermae of China were observed. 20 wood species of them from 12 genera and 7 families, had the crystals reported in this paper. The shapes of the crystals were able to be divided into 5 types. The shape, size and location of crystals proved to be of diagnostic value and taxonomic significance in woody anatomy. In specimens all crystals were determined to be calcium oxalate by EDAX analysis and histochemical tests. The amount of calcium element was over 99%. In 4 wood species the calcium crystals that were formed as a result of fungal metabolism of wood all along the hypha. It is the first report on the occurrence of silicondioxide in the inter layer of tracheids and ray paranchyma and bordered pit of Abies recurvata Mast., silica without any geometrical form. An EDAX analysis of the silica revealed elemental composition of Si: 93.75%, Na: 1.8%, K: 0.87%, Al: 1.42%, Ca: 7.3%. The origin and significance of crystals and silica also were discussed.

Key words: Crystals, Silica, Wood of species of Chinese gymnospermae