Perichaetial module reduced

The possibility that reduced perichaetial modules could be at the primary level of the branching hierarchy was considered, but in none of the plants examined was there convincing evidence of this. Similarly, all innovations produced on perichaetial modules appeared to develop into other perichaetial modules rather than vegetative primary modules (i.e., the sequence of module types is hierarchical and unidirectional). Individual primary modules often produce both perichaetial mod-... 

The morphological character pleurocarpy is viewed here in the strict sense, as the formation of archegonia on a reduced lateral module that has juvenile perichaetial leaves but lacks differentiated... 

---