^ / 



T/l/i^ 



Fig. 21. Sexual reproduction of Fnais, sh' wing the eight eggs (six in sight) 



charged from tlie oogonium and surrounded by a membrane (A), eggs liberated 

 from the membrane (E), antheridium containing sperms (C), the discharged lat- 

 erally biciliate sperms (G), and eggs surrounded by swarming sperms (F, H).— 

 After Singer. 



21 



