| Other lycophytes have a siphonostele, with a central region of generalized tissue within a cylinder of vascular tissue. |
| The thick-walled cells in the center of the core are sometimes considered to be pith, in which case the vascular arrangement would actually be a siphonostele. |
| Use the three-dimensional diagram to understand how a leaf gap relates to the vascular cylinder of a siphonostele. |
| In anatomical cross section, the stem of Lepidodendron displays an exarch siphonostele surrounded by secondary xylem in ranks. |
