Abstract: The major peptides in the seed of Taxus and Pseudotaxus have molecular weight about 31, 22 and 20 kilodaltons (Kd) shown by SDS polyacrylamide gel electrophoresis. The seed protein peptides of Cephalotaxus is very similar to those of Taxus and Pseudotaxus except a few bands of high molecular weight. Some considerable differences in peptide pattern exist between Amentotaxus and the three genera cited above. The former has a new major peptide, 33K, but lacks 22 K. The seed of Torreya does not contain peptide 44 K, although Torreya and Amentotaxus have many bands in common. To a certain extent, the seed protein peptides of Podocarpus nagi are similar to those of the above taxa. A great range of divergency in needle peroxidases among different genera of Taxaceae has been observed by using electrophoresis, while the zymogram of Cephalotaxus is somewhat similar to that of Taxus. Two series of protein data demonstrate, that there is an evolutionary tendency from Taxus to Torreya through Pseudotaxus and Amentotaxus within Taxaceae. And the Taxaceae is closely related to Cephalotaxus by way of Taxus. The systematic positionof the Taxaceae, therefore, should be placed under the Coniferales.

Key words: Taxaceae, Seed protein peptides, needle peroxidases, Systematic position