_ 18 - VAUCHERIA. 



37. Vegetative Stage. -Draw part of the thallus under the low power, showing : 

 colourless rhizoiis and green filaments. Draw part of the filament under the high power, 

 showing : cell- wall ; protoplasm ; chloroplasts ; mode of branching. 



38. Asexual Reproduction. Find a swollen end of a filament cut off by a cell-wall. 

 Draw this zoosporangium containing a single developing zoospore. Afterwards draw a 

 free swimming zoospore, showing : central region with chloroplasts ; clear outer region 

 with nuclei ; cilia. 



39. Sexual Reproduction. Draw under the high power part of a filament bearing 

 reproductive branches, to show : antheridium, cut off by cell-wall ; spermatozoids ; 

 oogonium, cut off by cell-wall ; ovum. Afterwards find and draw a fertilized ovum with 

 thick cell-wall. 



