PLATE LV. 



Figures magnified 500 diameters. 



PAGK. 



Figs. 1, 2 STAURASTRUM OPHIURA, Var. tetracerum, . . . 148 



Fig. 3. " Var. pentacerum, lighter form than 



Plate LIV, fig. 13, . 148 



" 4 STAURASTRUM LEPTOOLADUM, . . . .149 



" 5. Var. divergens, 



Figs. 6, 7. STAURASTRUM HELENEANUM, front and end views, . .146 



" 8, 9, 10. STAURASTRUM NANUM, three aspects, . . . 151 



" 11, 12. STAURASTRUM CORONULATUM, .... 148 



' 13, 14. STAURASTRUM ROTULA, end and front views, . . 148 



" 15, 16. STAURASTRUM PENTACL.ADUM, end and front views. (Com- 

 pare Plate LIV, fig. 15), . 149 

 " 17. 18. STAURASTRUM GRAI/LATORIUM, Var. ungnlatum, . .150 



Fig. 19. " typical form, . . 150 



Figs. 20, 21. STAURASTRUM FUSIFORME, front and end views, . . 150 



