Plate 13. 



Figs. l-fi. Ainphibkstrum coDstrictum Uliich and Bassler, 1904. (p. 44.) 



1. Portion of the incrusting zoarium, X 20, showing numerous ovicoUed zooecia, a giant 

 zooecium, and deformed primoserial zooecia. 



2. Nonovicelled zooecia, X 20. 



3. Zoarium, X 20, exhibiting the ancestrula, calcified zooecia and regenerated zooecia. 



4. Worn zooecia, X 20, exposing the dietellae. 



Pliocene (Waccamaw marl): Waccamaw River. Horry County, South Carolina. 



5. Drawing of se\'eral zooecia of the tyi)e specimens, X IT. 



6. A portion of the tj-jie specimen, X 20, showing zooecia with nontrifoliate opesia. The lateral 

 condyles are replaced by serrate denticles. 



Miocene (St. JIary's formation): Cove Point, Maryland. 

 Fig. 7. Amphiblestnim tenuiparietis. new species, (p. 4-5.) 



The incrusting type X 20. shotting tlie ancestrula and surro\inding zooecia, all with thin mural 

 rim. 



Miocene (Choctawhatchee marl): Jackson Bluff, Ocklocknee River, 25 miles southwest of Talla- 

 hassee, Florida. 

 Figs. 8-10. Ramplwnotus agellus T.lrich and Bassler, 1904. (p. 47.) 



8. The tj-pe specimen, X 20, showing the trifoliate opcsium and the avicularia oriented in the 

 zooecial axis. 



9. Drawing of a zooecium of the same, more enlarged. 

 Miocene (St. Mary's formation): Cove Point, Maryland. 



10. An example, X 20, containing both ovicelled and unovicelled zooecia. 



Miocene (St. Mary's formation): Bowler's wharf, 18 miles above Urbana, Middlesex County, 

 Virginia. 

 Figs. 11-13. Ramphonotus asperus, new species, (p. 4G.) 



11. Specimen, X 20, showing ovicelled zooecia, unovicelled zooecia with G spines and worn 

 zooecia exposing the dietellae. 



12. The incrusting zoarium X 20, illustrating the ancestrular region with several calcified zooecia. 



13. Another portion of the same specimen X 20, sho\ving both ovicelled and unovicelled zooecia, 

 and the dietellae. 



Miocene (Yorktown formation i Yorktown, ^'irginia. 



257 



