PLATE XL—Continued. 
FENESTELLA (PoLYrOllA) GRANILINEA. 
Page lot. 
Fig. 20. The non-celluliferous face of a frond, natural size. 
Fig. 21. A portion of the preceding, from near the base, showing branches wider than the fenestrules, and 
over the greater portion of the figure from two to three ranges of nodes. (X 6.) 
Fig. 22. An enlargement of a portion of the same frond at a distance from the base, showing the branches 
slightly wider than the fenestrules, but more angular than those of the preceding figure, and 
having but one range of nodes, forming a nodulose carina along the middle of the branch. 
(X 6.) 
Fig. 23. An enlargement from the celluliferous face of a frond, showing the comparative size of the 
branches and dissepiments, the carinate dissepiments, and the form and arrangement of the 
cell apertures. (X 6.) 
Upper Helderberg group. Ontario, Canada. 
