EXPLANATIONS AND REFERENCES, 

 PLATE CXXXIII. 



Figures magnified 250 diameters. 



PAGE. 

 Figs. 1, 2. SPIROGYRA WEBERI, Var. elonyata, .... 209 



" 3, 4. SPIROGYRA CALOSPORA, ..... 209 



Fig. 5-7. SPIROGYRA HASSALLJI, . . . . . .210 



Figs. 8, 9. SPIROGYRA INSIGNIS, . . . . . .210 



" 10, 11. SPIROGYRA HANTZSCHII, . . . . . .211 



