PLATE XVIII. 



Tolypella prolifera Leonbardi. 



FIG. 



1. Plant, two-thirds natural size, from Ramsey St. Mary, 



Huntingdonshire. 

 2, 3. Apices of dactyls, x c. 40. 



4. Fruiting branclilet. x c. 25. 



5. Oogonium. x c. 40. 



6. Oospore. x c. 40. 



