PLATE XXVI. 



FIGS. PAGE 



1-5. Closterium rostratum Ehrenb. 1-4, x 520; 



5, zygospore, x 200 (after Ealfs) . . 1 < s - s 



0-8. Cl. rostratum vav. Irrrlrosfralinn West. 0, x 



f>20; 7 and 8, zygospores, x 220 . IS'.i 



9_13._C7. setaceum Klirenb. 9-12, x 520 ; 13, zygo- 



spore, x 400 (after Half s) . .190 



