FILAMENTOUS GREEN ALGJE 



223 



365. CEdogonium. (Edogonium is an example of the second 

 kind of sexual reproduction. The thread-like plant is simple. 

 It grows in length by the repeated division of certain cells, the 

 marks of the successive divisions remaining on the cell wall near 



Fig. 177. 



Portion of thread of 

 oedogonium, showing 

 chlorophyll grains, and 

 peculiar cap cell walls. 



Fig. 178. 



Zoogonidia of CEdogonium escaping. 

 At the right one is germinating and 

 forming the holdfasts, by means of 

 which these algas attach themselves 

 to objects for support. (After Prings- 

 heim.) 



Fig. 179. 



CEdogonium undulatum, with 

 oogonia and dwarf males; the up- 

 per oogonium at the right has a 

 mature oospore. 



one end, giving a peculiar appearance as in fig. 177. In asexual 

 reproduction the content of a cell forms a single large zoospore or 

 swimming spore, with a crown of cilia near one end. After 

 escaping from the parent cell and swimming around it comes to 



