Plate 28. 
Figs. 1-12. Trelocycloecia torlilis Lonsdale, 1845. (p. 206.) 
I, 2. Fragments of the irregularly branched, cylindrical zoarium, natural size. 
3. Surface of a specimen, X 12, with a group of broken ovicells. The superior layer of the ovicells 
has disappeared in fossilization. 
4. A large isolated ovicell, X 12, with its upper surface broken away. 
5. Surface of ordinary zooecia, X 12, showing the mesopores grouped together in many parts of 
the branch. 
6. Same surface, X 25, illustrating the thickness of the zooecial walls. 
7. 8. Another surface, X 12 and a portion of the same, X 25, in which the zooecia have thin walls 
and the mesopores are arranged irregularly between the apertures. 
9. Outer portion of longitudinal thin section, X 25. 
10. Tangential thin section, X 25. 
II. Several zooecia of the same, X 100, showing that the internal walls are much calcified and 
are separated by a less dense tissue. 
12. Portion of a transverse thin section, X 25. 
Miocene (Yorktown formation): Yorktown, Virginia. 
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