PLATE XIII. 
Batostomella (/ran ulifera ( 1 tall). (Page 28.) 
[See also PI. XXIV, figs. 10, 11; PI. XXV, figs. 11, 12.] 
Fig. 1. Tangential sect ion, X 20, showing the solid interzocecial spaces and numerous 
acanthopores. 
2. Another tangential section, X 20, taken lower in the mature region where the 
acanthopores air smaller and the mesoporesare visible. 
3. Tangential section, X 30, si lowing the wall structure with the mesopores faintly 
visible. 
4, 5. Vertical section, x 20 and X 30, respectively, exhibiting the usual internal features 
Rochester shale. Lockport, N. Y. 
Bythopora spinulosa (Hall). (Page 29.) 
[See also PI. XXIV, tigs. 12, 13.] 
6, 7. Tangential and vertical seel ions, X 20. 
Rochester shale, Lockport, X. Y. 
TAoclema explanatum n. sp. (Page 33.) 
[See also PI. XXVI, fig. 4.] 
8. Surface of one of the types, X 10. 
9. Tangential section, X 20, showing the thin-walled zocecia, numerous mesopores, 
and comparatively few acanthopores. 
10. Vertical section, X 20, exhibiting the tabulation of zooecia and mesopores. 
Rochester shale, Rochester, X. Y. 
Lioclema circinctum n. sp. (1'age 34.) 
11. Vertical section, X 20, of the type specimen, showing two successive layers of zoircia. 
12. Tangential section, X 20, bringing out, the unusually numerous mesopores and 
apparent absence of acanthopores. 
13, 14. Small portion of fig. 12, X 00, and a portion of wall of same, X 75, exhibiting the 
peculiar wall structure. 
Rochester shale, Lockport, X. Y. 
Trematopora tuberculosa Hall. (Page 43.) 
[See also PI. XVII, figs. 1-3; PI. XXV, fig. IS.] 
15. A few zocecia of a vertical section, X 35, exhibiting the beadlike constrictions of 
the mesopores. 
16. Several zooecia of a tangential section, X 35, showing the minute structure of the 
walls and acanthopores. 
Rochester shale, Lockport, N. Y. 
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