PLATE CXLI. 



FIGS. PAGE 



l-3.Staurastrum Iceve Rails. 1*, X 510 ; 2, x 810 ; 



3, zygospore, X 520 . . .92 



4-7. St. inconspicuum Nordst. 4, X 590 ; 5, X 400 ; 

 6, x 1000 ; 7, zygospore X 600 (after Liitke- 

 miiller) . . . .86 



8.- St. inconspicuum var. crassum Gay. X 520 . 87 

 9-10. St. bacillare Breb. 9. X 400 ; 10, X 400 (after 



Ralfs) . . . . .84 



11-12. St. bacillare var. obesum Lund. 11, X 400 (after 



Lundell) ; 12, X 400 . .84 



13. St. bacillare var. undulatum var. nov. X 520 . 85 

 14-15. St. brachiatum Ralfs. 14, X 520 ; 15. zygospore, 



X 520 . . . ' .88 



IQ.St. nodosum W. & G. S. W. X 660 . . 88 



17-18. St. Icevispinum Biss. 17, X ? (after Bissett) ; 18, 



a form, x 520 . . . .90 



19. St. sublcevispinum W. & G. S. W. X 520 (front 

 view too long in proportion, because cell- 

 division is just about to take place) . .91 

 20. St. subnudibrachiatum W. & G. S. W. X 520 . 91 

 21. St. asperum Breb. Zygospore, X 400 (after Ralfs) 74 



