Abstract:The primary xylem of plump taproot of Aconitum finetianum is the diarch with xylem in the center.In the action of the secondary structure of the herb ,the meristem is first produced in the secondary phloem,then the anomalous cambium is produced in the secondary xylem forms a new and splits into anomalous structure.In the action of anomalous structure of the herb,the meristem in the secondary phloem sinks inwardly from many sites,and forms many rings with the anomalous cambium.One of these rings forms a special endodermis and the protostele turns into the schizogenous stele.