The structure and reproduction of
Compsopogon iyengarii Krishnamurthy collected from the river Yamuna at Allahabad have been studied both in nature and cultures. Certain branches produced by proliferating cortical cells may bear monoaplanospore like structures. Monoaplanospores and microaplanospores may germinate
in situ under cultural conditions. Stages in development and germination of microaplanospores have been investigated.