Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
Fig. 
PLATE XLVI—Continued. 
Fenestella VERRUCOSA. 
Page no. 
22. An enlargement from the non-celluliferous face of a frond, showing irregular branches. 
23. An enlargement from the celluliferous face of a frond, showing the disposition of the Cc.ll aper¬ 
tures, and the nodes along the middle of the branch. (X 6.) 
24. An enlargement of a transverse section of the branches. (X 6.) 
Upper Helderberg group. Falls of the Ohio river. 
FeNESTELLA T U B E RC U L A T A. 
Page 116. 
25. A fragment, natural size. 
26’. An enlargement from the preceding, showing more distinctly the form and disposition of the 
branches and dissepiments, and the prominent nodes. (X 6.) See tigs. 33, 34. 
Upper Helderberg group. Walpole, Ontario, Canada. 
Fenestella jequaliS. 
Page 112. 
27. An enlargement from the non-celluliferous face. (X 6.) 
28. An enlargement from a specimen which has the celluliferous portion of the branches covered by 
a rock deposit; the carina, with prominent nodes alone being exposed. (X 6.) 
29. An enlargement of the lateral view of a branch, showing the nodes on the non-celluliferous face. 
(X 6.) 
30. An enlargement from the celluliferous face ; the branch on the right has been macerated and the 
organic matter removed, leaving the siliceous tilling of the cavity of the branch and of the cell 
tubes. (X 6.) 
31. An enlargement from the non-celluliferous face, the branches being partially imbedded in the 
rock. The branches are straight, sinuous or zig-zag, according to the position of the dissepi¬ 
ments, whether alternating or opposite. (X 6.) 
Upper Helderberg group. Falls of the Ohio river. 
FENESTELLA TUBE RCU LATA. 
Page 116. 
33. An enlargement of a lateral view of a branch. (X 6.) 
34. An enlargement from the non-celluliferous face, showing striated branches and prominent nodes. 
(X 6.) See tigs. 25. 26. 
Upper Helderberg group. Walpole, Ontario, Canada. 
Fenestella rroceritas. 
Page 115. 
32. A fragment, natural size. 
35. An enlargement from the non-celluliferous face. (X 6.) 
36. An enlargement from the celluliferous face. (X 6.) 
Upper Helderberg group. Walpole, Ontario,-Canada. 
