Plate 11. 
Figs. 1-3. Acanthodesia savarti Audouin, 1826, forma typica. (p. 31.) 
1. An incrusting specimen X 20, of the typical form of the species, illustrating the considerable 
micrometric variations. Traces of the spicules in the opesium are visible. 
Miocene: Bowler’s wharf, 18 miles above Urbana, Middlesex County, Virginia. 
2. An example X 20, with young zooecia. 
3. Surface of a free, multilamellar zoarium, X 20, with numerous spicules, in the opesium. 
Miocene (Yorktown formation): Near Suffolk, Virginia. 
Fig. 4. Acanthodesia savarti forma bifoliata Ulrich and Bassler, 1904. (p. 33.) 
Surface of the bilamellar type zoarium, X 20, showing the thin mural rim, the absence of the cryp¬ 
tocyst, the tubercles at the angles and and spicules in the opesium. 
Miocene (Choptank formation): Jones Wharf, Maryland. 
Figs. 5-9. Acanthodesia savarti forma delicatula Busk, 1859. (p. 33.) 
5. An incrusting example, X 20, referred to this form. 
Miocene: Bowler’s wharf, 18 miles above Urbana, Virginia. 
6. Zoarial fragments, natural size. 
7. A branch, X 20, on which the zooecia are developed in opposite directions. 
8. Another branch, X 20, in which the cryptocyst is small and the superficial ornament is ob¬ 
scured by fossilization. 
9. A well preserved branch, X 20, showing the unequal development of the cryptocyst. 
Miocene (Choctawhatchee marl): Jackson Bluff, Oeklocknee Biver, 25 miles southwest of Talla¬ 
hassee, Florida. 
Figs. 10-12. Membrendoecium grande, new species, (p. 36.) 
10. Portion of the zoarium X 20, with irregular zooecia, one showing the endozooecial ovicell. 
Miocene (Duplin marl): Wilmington, North Carolina. 
11. Marginal, elongated zooecia, X 20. 
12. Another portion of the same zoarium X 20, with several ovicelled zooecia. 
Pliocene (Waccamaw marl): Waccamaw River, Horry County, South Carolina. 
255 
