PLATE XXXVII. 



FbHSSTELLA (PoLTPORA) KOBU8TA. 



Page 1S6. 



See Plates 34, 39 and 46. 



Pl^. 1. An enlargement of the non-celluliferous face, showing (lecideilly angular ami carinated branches 

 and dissepiments. (X 6.) 



Upper Helderberg group. IValpole, Ontario, Canada. 



FeNE8TKL1<A (PoLYPOUA) DI8TAN8. 



Page 161. 



See Plate 44. 



Fig. 2. An enlargement of a portion of tig. 3, showing more distinctly the form of the branches, the 

 prominent distant no<les and tine indistinct striations. (X 6.) 



Fig. 3. The non-celluliferous face of a fi-ond, showing the size of branches and dissepiments, and mode of 

 growth. 



Pig. 4. An enlargement of the non-celluliferous face of another specimen ; a.s compared with fig. 2, the 

 branches are more slender ami destitute of nodes, and the stnation.s are stronger. (X 6.) 



Fig. 6. A jwrtion of the celluliferous face of a specimen, enlarged, showing the form and arrangement of 

 the cell ai)ertures and the intermediate interrupted striie. (X 6.) 



Fig. 6. The non-cellulifei-ous side of a specimen, natural size. 



Fig. 7. A iK)rtion of fig. 6, enlarged, showing more distinctly the character of the branches and dissepi- 

 ments, and the fine indistinct striation of the branches. (X B.) 



Pig. 8. An enlargement of a portion of the celluliferous face of another specimen, showing the form and 

 aiTaiigement of the cell apertures and the indistinct intermediate strise ; the elevated margins 

 of the cell apertures are obliterated by weathering or maceration. (X 6.) 



Fig. 9. The celluliferous face of another specimen, natural size. 



Fig. 10. An enlargement of a portion of tig. 9 ; the specimen i.s much more macerated than that repre- 

 sented by fig. 8, the branches flatter and the cell apertures open obliquely ; the dissepiments 

 are channeled. 



Fig. 15. A specimen, natui-al size, showing the arrangement of the branches and dissepiments, and their 

 manner of growth. 



Vig. 16. An enlargement of a portion'of fig. 15, showing more distinctly the character of the branches and 

 dissepiments, and their comparative size. (X 6.) 



Upper Helderberg group. I!fear Buffalo, N. Y. 



Fenestella (Polypora) flabelliformis. 



Page 161. 

 Fig. 11. The celluliferous face of a frond, natural size, showing the disposition of branches and dissepi- 

 ments, and manner of growth. 

 Fig. 12. An enlargement of a portion of flg. 11, showing more distinctly the comparative size of the 

 branches and dissepiments. The branch on the light is in a pei-fect condition, and shows the 

 form and arrangement of the cell apertures, the comparatively .strong ridges sepai-ating the 

 ranges of ai)ertures, and the interrupted striations. The surface of the other branch has been 

 macerated and removed, showing the polygonal cells below. (X 6.) 

 Upper Helderberg group. Oiumdaga Valley, N. Y. 



Fenestella (Polypora) peranoulata. 

 Pa^ les. 

 Pig. 13. The non-celluliferous face of a frond, showing the disposition of the branches and dissepiments, 



and mode of growth. 

 Pig. 14. An enlargement of a jjortion of the preceding. (X 6.) The branches should appear more 

 sngfular than \n represented in the figures. 



Upper Helderberg group. Western New York. 



