Taxonomy of Chara Braunii: An Experimental Approach1

SUMMARY Results from the present study suggest that Chara braunii encompasses a complex of geographical races or incipient species that although morphologically similar, are isolated to varying degrees ranging from partial interfertility to complete reproductive incompatibility. Most of the 6 clones studied were interfertile to the extent that fertilization was followed by the development of black oospores, but subsequent germination tests disclosed that many of these either failed to germinate or gave rise to offspring that were partially or completely sterile. No support was encountered for the suggestion that C. braunii is of recent development or that it has been distributed rapidly throughout the world.