184 SEANCE DU 14 AVRIL 1899. 



Pritchard (A.), A history of Infusoria including the Desmidiaceae and Diato- 



macea?, British and Foreign. London, 1861. 

 Habenhorst (L.), Flora Europaea Algarum. Sect. III. Leipsig, 1868. 



— Deutschlands Kryptogamenflora, Algen. Leipsig, 1847. 

 Balfs (J.), The British Desmidieae. London, 1848. 



Toni (J.-B. de), Sylloge Algarum omnium hucusque cognitarum. Patavii, 1889. 

 Wolle (F.), Desmids of the United States. Bethlehem, 1884. 



Explication ties figures de la planche III de ce volume. 



Fig. 1. — Spirogyra tolosana sp. nov. — Cellules renfermant les zygo- 

 spores. 



Fig. 2. — Spirogyra tolosana sp. nov. — Cellules vegetatives. 



Fig. 3. — Spirogyra tolosana. — Filaments fructifies. (Grossissement plus 

 faible.) 



Fig. 4. — Closterium macilentum Breh. — Cellule vide. 



Fig. 5 et 6. — Closterium macilentum Breb. — Cellules vivantes. 



Fig. 7. — Closterium calosporum Lund. — Cellule vivante. 



Fig. 8. — Closterium calosporum Lund. — Cellule vide. 



Fig. 9 et 10. — Disphinctium curium Reinsch. 



Fig. 11 et 12.— Pleurotceniopsis pseudoconnata Lagerh. 





