Plate 10. 
Figs. 1-3. Acanthodesia oblongula I lrich and Bassler, 1904. (p. 34.) 
1. One of the original types of this incrusting species, X 20. illustrating the prominent inter- 
zooecial tubercles and the spinose processes (spicules) surrounding the opesium. 
Miocene (Calvert formation 1 ): Plum Point, Maryland. 
2. A specimen, X 20, showing the interzooecial tubercles joined. 
Miocene (Choptank formation): Pawpaw Point, Maryland. 
3. Another of the original types, X 20, in which there are numerous spinose processes but with the 
interzooecial tubercles little developed. 
Miocene (Choptank formation): Governor Run, Maryland. 
Figs. 4-5. Vibracellina pusilla, new species, (p. 35.) 
4. Ancestrular region of the incrusting zoarium, X 20. 
Miocene (Duplin marl): Natural Well, 2 miles southwest of Magnolia, North ( arolina. 
5. A well-developed zoarium, X 20, illustrating normal and regenerated zooecia and the small 
but salient vibracula. 
Pliocene (Caloosahatchee marl): Shell Creek, De Soto County, Florida. 
Figs. 6-7. Vibracellina simplex, new species, (p. 35.) 
6. The incrusting zoarium, X 20, showing the ancestrular region. The vibracula are very rare 
but heterozooecia are present. 
Miocene (Choctawhatchee marl): Jackson Bluff, Ocklocknee River, 25 miles southwest of Talla¬ 
hassee, Florida. 
7. A small zoarium, X 20, showing the calcified ancestrula which engenders five zooecia. 
Several regenerated zooecia are present. 
Miocene (Duplin marl): Natural Well, 2 miles southwest of Magnolia, North Carolina. 
Fig. 8. Conopeum germanum Ulrich and Bassler. 1904. (p. 27.) 
The incrusting type specimen, X 20, illustrating the interopesial cavities and other character¬ 
istics. 
Miocene (Choptank formation): Dover Bridge, Maryland. 
Fig. 9. Hemiseptella filimargo, new species, (p. 71) 
The incrusting type specimen, X 20. The salient rim separating the zooecia and the two large 
lateral as well as the smaller spicules of the opesium are evident . 
Miocene (Yorktown formation): York River, Virginia. 
Fig. 10-14. Membranipora flabellata Canu, 1904. (p. 20.) 
10. Surface of an outer lamella, X 20, with the tubercles worn away and the zooecia grouped 
around a false ancestrula. 
Miocene (Yorktown formation): Yorktown, Virginia. 
11. Portion of a zoarium, X 20 , with the zooecia separated by interopesial cavities. 
12. Young zooecia, X 20, with thin mural rims. Other zooecia of this same zoarium are normal, 
tuberose or separated by interopesial cavities. 
13. Zooecia, X 20, with granulose mural rims. 
Miocene (Yorktown formation): Near Suffolk, Virginia. 
14. Photograph of an inner lamella, X 20, with the tubercles preserved. 
Miocene (Yorktown formation) Yorktown, Virginia. 
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