PLATE XXXV. 



FIGS. PAGK 



1. Euastrum oblongum (Grrev.) Ralfs var. cephalo- 



phorum West, x 400 . . .14 



2. E. oblongum. Zygospore, x 220 . . 14 



Z-l.E. Didelta (Turp.) Ralfs. 3, 5, and 6, x 430; 



4, x 220; 7, zygospore, x 220 . 15 



8-10. E. ampullaceum Ralfs. 8 and 9, x 520 ; 10, 



zygospore, x 390 . . .19 



11-12. E. affine Ralfs. 11, x 400 (after Ralfs); 12. 



x 430 17 



