PLATE V. [PAGE 70.] 

 FRESHWATER ALGJB. 



Fig. 



1. Conferva floccosa, single filament. 



2. Lyngbya muralis, single filament. 



3. Ulothrix mucosa (?), filament. 



4. Synedra radians, prepared frus- 



tules. 



5. Synedra radians, tuft of natural 



frustules. 



6. Cladophora crispata, with zoo- 



spores (a). 



7. Batrachospermum moniliforme, 



portion of filament. 



8. Batrachospermum moniliforme, 



filament. 



9. Closterium acerosum. 



10. Draparnaldia glomerata. 



11. Spirogyra quinina. 



12. Spirogyra nitida, filaments con- 



jugating. 



13. Zygnema cruciata. 



14. Coleochfete scutata. 



15. Xanthidia in flint. 



16. Micrasterias rotata. 



17. Gomphonema acuminatum. 



I Fig. 



18. Gomphonema acuminatum, pre- 



pared frustules. 



19. Ankistrodesmus falcatus. 



20. Pediastrum Boryanum. 



21. Hyalotheca dissiliens. 



22. Pinnularia viridis. 



23. Fragilaria capudna. 



24. Fragilaria capudna, prepared 



frustules ; s* side view of F. 

 virescens. 



25. Scenedesmus quadricauda. 



26. Schizoffonium, probably a form of 



Lyngbya. 



27. Campylodiscus costatus. 



28. Nitzschia minutissima, front view. 



29. Nitzschia minutissima, valves. 



30. Epithemia turgida. 



31. Diatoma elongatum, natural frus- 



tules. 



32. Diatoma elongatum, prepared frus- 



tules. 



33. Cocconeis placentula. 



