1'LA.TE LVIII— (Joiitinuca 



FiSTULIPOKA SCROBICULATA. 



Page 212. 



Fig. 17. An enlargement, showing the form and disposition of the cell apei-tures and interapertiii-al i)its, 



and a portion of one of the mac.ulaB destitute of cell apertures. (X S.) 

 Fig. 18. A still farther enlargement, showing moi-e distinctly the form of the cell apertures and inter- 

 ai>ertural pita. (X 18.) 



Hamilton group. York, Livingston county, N. Y. . 



FiSTULIPOKA PLANA. 



Page 215. 

 Fig. 19. An enlargement, showing the form and disposition of the cell apertures ; the specimen is covered 

 with a thin incrustation which obscui-es the interapei-tural pits over a portion of the surface. 

 (X6). 

 Fig. 20. A still farther enlargement, showing more distinctly the form of the cell apertures. (X 18.) 

 Hamilton group. Near CanaTidaigtM Lake, N. Y. 



FaVICELLA INCLU8A. 

 Page 234. 

 Fig. 21. An enlai-gement, showing the foi-m and disposition of the cell apertui-es, the angular elevations 

 suiTOuniling them, the interapertural pita, and the monticules, the centers of which ai-e desti- 

 tute of cell apertures. ( X 6. ) 

 Pig. 22 A still farther enlargement, showing nid-e distinctly the cell apertui-es, the suiTOunding eleva- 

 tions and interapertural pits. (X 18) 

 Fig. 23. A vertical section, showing the manner of gprowth of the cell lubes and the intermediate vesicu- 

 lose structure. (X 6 ) 



Hamilton group. York, Liviiigston county, N. Y. 



