PLATE XI. 



FIGS. PAGE 



l-3Closterium Cynthia De Not. 1 and 2, forms, 

 x 520; 3 a, x 400 (after De Not,); oa, 

 x 400 ' . H3 



4. Cl. Cynthia var. cui"vatissimum West & G. S. 



West, x 520 . . .114 



5_7._CfZ. Lagoense Nordst. 5, x 400 (after Nord- 



stedt). 6 and 7, x 520 . . .114 



8-10. Cl. Ai-cheriaiinm Cleve. 8, x 400 (after 

 Lundell) ; 9, x 400: 10, zygospore, x 400 

 (after Liitkemiiller) . H ; > 



11. Cl. Arrln'riauiim forma, X 520 115 



12. CL porrectum Nordst, x 400, after Nordstedt 116 

 13. CL porirctum var. anguntatum West & G-. S. 



West, x 520 . . . .116 



