. PLATE XXXIII. 



Figures magnified 500 diameters. 



PAGE. 



Fig. 1. ECASTRUM WOLLEI, .... . 108 



" 2. ' transverse view of semi-cell. . . 108 



" 3. " " Var. cuspidatum, . . . .108 



Figs. 4, 5. lateral and end views, . 108 



" 6-8. EUASTRUM INERME, three forms, * 115 



" 9, 10. EUASTRUM DIDELTA, two forms, . . . .109 



" 11, 12. EUASTRUM ANSATUM E. Ralfsii, . . . 109 



