PLATE LV. 



Figures raagnifled 500 diameters. 



Page. 



Pigs. 1, 2. Staurastrpm Ophiura, Var. tetracerum, . . . 148 



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



Plate LIV, fig. 13, 148 



" 4 STAtTRASTRDM UEPTOCLADnM, . . . 149 



" 5. " " Var. divergens, . . — 

 Figs. 6, 7. Staurastrum Heleneantjm, 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 pentacladum, end and front views. (Com- 

 pare Plate LIV, fig. 15), . 149 

 " 17. 18. Staurastrum qrallatorium, Var. ungulatum, . . 150 

 Fig. 19. " " typical form, . . 150 

 Figs. 20, 21. Statjrastrum fusiforme, front and end views, . . 150 



