subrhombicum,etc. On the basis of the floral composition,the geological age of the Yangshan Formation flora belonged to the late Early Carboniferous epoch,corresponding approximately to late Visean to early Namurian A.

• 根据植物群的总体组成，杨山组植物群的地质时代属于早石炭世晚期，大致相当于维宪晚期至纳缪尔A期。