Plate 123 



Fig. 1. Cylindrospermum stagnale var. angustum G. M. Smith, 



x495 



Figs. 2, 3. Aulosira laxa Kirchner, x 530 



Figs. 4, 5. Scytonema alattim ( Carm. ) Borzi: 4, x 750; 5, x 400 



Figs. 6, 7. Scytonema Archangelii Bornet & Flahault: 6, x 210; 7, x 

 300 



Figs. 8, 9. Scytonema tolypothricoides Kuetzing, x 600 



[906] 



