PLATE "LIT, 



Figures magnified 500 diameters. 



PAGE. 

 Fig. 1. STAUKASTRUM QUADRANGULARE, a Minnesota variety, . 160 



; 2. a Pennsylvania and New 



Jersey variety, . . 160 



Figs. 3, 4. end view of Florida forms, 160 



' 5, 6. STACRASTRUM CRENATUM, . . . . .138 



Fig. 7. STAURASTRUM LONGISPINUM, .... 160 



Figs 8, 9, STAURASTRUM SPINOSUM. See St. furcatum and Kitchdii, . 152 



" 10, 11. STAURASTRUM PULCHRUM,* .... 147 



" 12, 13. STAURASTRUM INCISUM, ..... 146 



Fig. 14. " " six rayed form, ... 146 



Figs 15, 16. STAURASTRUM DISTENTUM, ..... 165 



" 17, 18. STAURASTRUM ELOISEANUM, . . . .164 



" 19-25. STAURASTRUM ENORME, . . . . .166 



" 26-28. STAURASTRUM ALTERNANT, .... 142 



" 29. 30 STAURASTRUM SCABRUM, . . . . .144 



" 31-36. STAURASTRUM MARGARITACEUM, . . . . 138 



" 36-38. STAURASTRUM TRICORNE, . . . . .138 



" 39, 40. STAURASTRUM PANICULOSUM, . ... 137 



" 41, 42. STAURASTRUM RUGULOSUM, ..... 140 



" 43-45. STAURASTRUM PTTNCTULATUM, . . . . 141 



* Compare note under St. incisum, p. 146. This species from ponds, New Jersey, 

 was described in the " Bull. Tor. Bot. Club, New York, 1880." Membrane smooth ; 

 end view flve-rayed; apices of rays obtusely rounded, bases wide, separated by a 

 rounded sinus. 



