PLATE XXXVII. 



Figures magnified 375 diameters. 



Page. 



Fig. 1. MiCHASTERIAS Jenneri, ...... 127 



" 2. " " Var. angulosa, . . 127 



Figs. 3, 4. MiCBASTERiAS osciTAifS, two semi-cells, varying mainly in the 



apices of the polar lobes ; in the one 



simple, in the other divided, . . 128 



" 5, 6. MicRASTEKiAS DECEMDENTATA, a large form, two sizes, . 126 



" 7, 8. MiCRASTERiAS CRENATA, two forms, . . . 126 



