ANATOMY OF CORTEX AND SECONDARY PHLOEM OF ROSACEAE. 8. ROSOIDEAE: DRYADEAE--GEEAE GROUP

摘要

The cortex and phloem anatomy in the species of Acomastylis, Coluria, Dryas, Eryihrocoma, Geum, Novosieversia, Orthurus, Parageum, Purshia, Sieversia, and Waldsteinia does not fully confirm any available version of group taxonomy. Four groups of equalranks could be assembled on the base of phloem design: Purshia- (Purshia), Dryas- (Dryas), leptorhizomatous herbs-(Sieversia) and pachyrhizomatous herbs-group (the others). The latter may be divided into Waldsteinia-(Waldsteiriia) and Geum-subgroups, Acomastylis, Eryihrocoma, and Novosieversia might be rearranged into one genus closely related to Coluria and Orthurus which we considered as one genus too. No one of (hem would be combined with Geum. The phloem design gives no reason to include Sieversiaintp Geum. Siewrsia is similar to shrubby representatives of the group because of its arborescent phloem pattern.