PLATE LXIII. 
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Stictopora subcarinata. 
Page 261. 
1. A fragment, natural size. 
Hamilton group. Bellona, Yates county, N. Y. 
2. An enlargement from a decidedly angular specimen, showing the form and arrangement of the 
cell apertures, and a single ridge along the middle of the branch. (X 6.) 
3. A still farther enlargement, showing more distinctly the character of the cell apertures. (X 18.) 
4. An enlargement from another branch of the same frond, showing a more flattened form, and a 
more irregular disposition of the cell apertures. (X (3.) 
Hamilton group. Darien Centre, Genesee county, N. Y. 
5. An enlargement from another frond, showing several ranges of apertures separated by striations 
or ridges. (X 6.) 
6. A still further enlargement, showing more distinctly the longitudinal ridges and the character of 
the cell apertures. (X 18.) 
Hamilton group. Bellona, Yates county, N. Y. 
Acrogenia frolifera. 
Page 267. 
7. A frond, natural size, showing the rootlets and manner of growth. 
8. An enlargement from the preceding, showing more distinctly the character of the roots. (X 3.) 
9. An enlargement of the base of a branch, showing the conical, truncated apex, and the striated 
portion above. (X 6.) 
Hamilton group. Vicinity of Muttonville, North Bristol township, Ontario county, N. Y. 
10. An enlargement from near the base of a branch from another frond, showing a different character 
of striation from the preceding. (X 0.) 
11. A still further enlargement from near the margin, showing the character of the striation. (X IS.) 
Hamilton group. One mile north of Pavilion Village, Genesee county, N. Y. 
12. An enlargement, showing the conically truncated base, striated longitudinal ridges, with ranges 
of cell apertures between them. (X 6.) 
Hamilton group. Near Lodi Landing, Seneca lake, N. Y. 
13. An enlargement, showing the form and arrangement of the denticulated cell apertures, and the 
longitudinal ridges. (X 0.) 
Hamilton group. Darien Centre, Genesee county, N. Y. 
14. An enlargement, showing prominent denticulations which have the appearance of circular cell 
apertures. (X 6.) 
Hamilton group. Eighteen-mile-creek, Erie county, N. Y. 
15. Enlargements of transverse sections from different portions of a branch, a, near the apex, b, a 
little above, c, from the flattened part of the branch. 
Hamilton group. Vicinity of Muttonville, North Bristol township, Ontario county, N. Y. 
Stictopora pekmarginata. 
Page 258. 
16. An enlargement, showing the form and arrangement of the cell apertures. (X 18.) 
Hamilton group. West Hamburg, Erie county, N. Y. 
Stictopora bifurcata. 
Page 254. 
17. An enlargement, showing the mode of growth, the form and arrangement of the cell apertures, 
and the longitudinal nodose ridges. (X 6.) 
Hamilton group. Near Muttonville, North Bristol township, Ontario county, N. Y. 
