Plate II. 



7. VauchMa, Sexual reproduction ; 



2 „ Zygospores formed in one filament "■ Antherid.um o. Oogonium 



' . . ^ s. Spermatozoids 



3 „ Gcrmmation of zygospore ^ 



4. Vaucheria ...nlh, branched filament 8, 9, 10, 11, Vd^ox ghhator. See text. 



with root processes 12 to 19. Desmid. Cmmarium botrytis 



5. „ Asexual reproduction ; zoospore Propagation by division (Figs. 13 to 15) 



escaping Sexual Veproduction (Figs. 16 to 19i 



6- „ Zoospore free 20. Desmid. Cloiurium lunula 



'21. Diatom, ^innularia >irldis 



