246 



FOUNDATIONS OF BOTANY 



continuity of the cell-cavity and (in young plants growing on soil) 

 search for root-like portions, in those growing in water for branch- 

 ing portions, and fruiting, organs in the form of swellings or short 

 lateral branches. 



With a power of about thirty to sixty diameters sketch a selected 

 plant of moderate extent as nearly complete as possible or else 



Fig. 180. — Vaucheria synandra. 



A, a filament with archegonia and antheridia (considerably magnified) ; B, part 

 of same much more highly magnified ; o, oogonium ; a, antheridium ; C, a 

 later stage of B; B, end of a filament with a zoospore, z, escaping (highly 

 magnified). 



sketch a portion showing the branching and a root-like portion. 

 Note and indicate the absence or presence and arrangement of 

 chlorophyll. Can Vaucheria probably use carbon dioxide ? 



284. Reproduction in Vaucheria. — Make an outline sketch of 

 fruiting organs, if found. See if any filaments can be found with 

 the contents massing or escaping at the tips. In some species 



