EXPLANATIONS AND REFERENCES, 



PLATE LXXIV. 



Figures magnified 250 diameters. 



PAGE 



Figs. 1, 2. OEDOGONIUM CRYPTOPORUM, Var. vulgare, . . . 70 



Fig. 3. OEDOGONIUM OBSOLETUM, . . . . .71 



" 4-6. OEDOGONIUM FRAGILE, . . . . . .71 



Figs. 7, 8. OEDOGONIUM ZIG-ZAG, . . . . .71 



" 9, 10. OEDOGONIUM VERNALE, . . . . . .71 



Fig. 11-14. OEDOGONIUM CRISPUM, Var. ro&iellatum, ... 72 



u 15. " " type form, . . 72 



' 16-19. OEDOGONIUM POLYMORPHUM, .... 73 



Figs. 20, 21. OEDOGONIUM PLUSIOSPORUM, . . . . .72 



