PLATE II. 

 FENESTELLA. 



' (Page 500.) 



Fig. 1. Celluliferous face, showing low, smooth carina. x6. Group a. 



Fig. 2. Celluliferous face of a form showing a row of nodes between 

 the rows of apertures. x6. Group /9. 



Fig. 3. Celluliferous face, with prominent carinse expanded at the 

 summit. x6. Group e. 



Fig. 4. Transverse section of a form belonging to group a. 



Fig. 5. Oblique view of a portion of the celluliferous face of F. 

 * stellata, showing the very prominent stellate nodes. x6. 



Fig. 6. A transverse section of a branch showing conical nodes. x6. 



Fig. 7. Side view of a branch of F. exornata, showing the prominent, 

 thin carina. x6. 



Fig. 8. End view of branches of the same species. x6. 



Fig. 9. Side view of a branch of F. latijunctura^ showing the charac- 

 teristics of the carinse of Group d. 



Fig. 10. End view of branches of the same species. x6. 



Figs. 11, 12. End view of branches of F. M-imbricata and F. lati- 

 carina, showing the characteristics of Group £. x6. 



Fig. 13. An enlargement from the celluliferous face of a specimen, 

 showing the characters of the caringe of Group C. 



Figs. 14-17. Fragments of specimens, natural size. 



Fig. 18. An enlargement of the- base of a frond of F. variapora, 



622 



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