PLATE XLIV. 
Fe NEST ELL A DISPANDA. 
Page 111. 
Fig-. 1. A fragment, showing the comparative size of the branches and dissepiments and manner of 
growth, natural size. 
Fig. 2. An enlargement of a portion of the non-celluliferous face of a frond. (X 6.) 
Fig. 3. An enlargement of a portion of the celluliferous face of a frond, showing the form and arrange¬ 
ment of the cell apertures. (X (5.) 
Fig. 4. An enlargement of a portion of the celluliferous face of another frond, showing a somewhat more 
lax mode of growth than the preceding specimen ; the cell apertures are more widely sepa¬ 
rated, and the intermediate surface of the branch is tinely striated. (X 6.) 
Upper Helderberg group. Western New York. 
FENESTELLA SINUOSA. 
Page 116. 
Fig. 5. r J Phe celluliferous face of a frond, natural size. 
Fig. 0. An enlargement of a portion of the same frond, showing the form and arrangement of the cell 
apertures and the sinuous carinse. (X 6.) 
Upper Helderberg group. Near Caledonia, N. Y. 
Fenestella (Polypora) distans. 
Page 161. 
See Plate 37. 
Fig. 7. A small fragment, showing the strong striated branches connected by slender dissepiments. (X 6.) 
Upper Helderberg group. Near Buffalo, N. Y. 
FEXESTELLA parallela. 
Page 107. 
Fig. 8. A portion of a frond, natural size, showing the appearance of the non-celluliferous face under 
different degrees of weathering. 
Fig. 9. A part of another well-preserved frond, natural size, showing angular branches and dissepiments. 
Fig. 10. A lateral view of a branch without nodes. (X 0.) 
Fig. 11. A lateral view of a branch, showing nodes perfectly preserved. (X 6.) 
Fig. 12. A portion of the non-celluliferous face of a frond, showing angular branches and slightly curved 
dissepiments. (X 6.) 
Fig. 13. A portion of the celluliferous face of a frond, without nodes. The elevated margins of the aper¬ 
tures being well preserved it is not probable that this specimen was ornamented with nodes. 
(X 6.) 
Fig. 14. A portion of the celluliferous face of a frond, showing distinct nodes on the carinse and oblique 
cell apertures with prominent elevated margins. (X 6.) 
Fig. 15. A portion of the celluliferous face of a frond showing nodiferous carinse, more prominent cell 
apertures, and generally a more robust appearance than either of the preceding specimens. 
(X 6.) 
Fig. |16. A portion of the non-celluliferous face of a frond. This specimen has been so much weathered 
that the carinse have disappeared, leaving a slight narrow channel along the middle of the 
branches. (X <3.) 
Fig. 17. A specimen where the branches and dissepiments have been removed by solution. The illustra¬ 
tion shows the filling of the fenestrules and cells. (X 15.) 
Fig. 18. A portion of the non-celluliferous face of a frond, weathered so as to show the fibrous structure 
composing the more solid portion of the branches. (X 6.) 
Upper Helderberg group. Near Buffalo, N. Y. 
