PLATE XLII. 



Figures magnified 300 diameters, excepting the Micrasterlas only about 

 one-half as much. 



PAGE. 

 Fig. 1. MICRASTEKIAS SwAiNEi, Hastings, . . . .119 



" 2. MICRASTERIAS KiTCHELii, Wolle, variety. Pond, Malaga, 



New Jersey, . . .129 



Figs. 3-5. XANTHIDIUM ANTELOPAEUM, Kg., . . . . 101 



Var. truncatum, Hastings, front, 

 lateral and end views, . 101 



" 6, 7. STAURASTRUM MEGALONOTUM, Nord., . . . .141 



Var. obtusum, Hastings, . 141 



Nord.'s Spitz., Des. Arcto. and Des. Groen. 



" 8-11. STAURASTRUM CRESCENTUM, Hast., front and end views, . 153 

 " 12, 13. EUASTRUM VERRUCOSUM, Ehrb., .... Ill 



Var. simplex, Joshua, . .111 



" 14, 15. STAURASTRUM SAXONICUM, Bulnh., . . . 154 



Var. pentagonum, Wolle, front 

 and end views, . . .154 



" 16, 17. EUASTRUM HASTINGSII, Wolle, . . . .113 



