Plate 57. 



Figs. l-o. ilftrivlDJiuiii trdnsrcrmnii, new speoies (]i. 444 1. 



1. The free bilainellar zoariiim, natural size. 



2. Surface of the same specimen. X 20. Some of the zooecia have oral avicularia. 



3. Another zoarinm, X 20, showing some zooecia with lateral rininlo and others with 



a convexity on the proximal border, which increases the transverse aspect of the 

 )ieristomice. 

 .Alidille Jacksonian (Castle Hayne limestone) : Wilmington, North Carolina. 

 Cat. No. 64120, U S.N.M. 

 Figs. 4-10. Mctradolittm ohliiiiiiDii. new species (p. 44G). 



4. Fragment of the bilamellar zoarium, natural size. 



5. Half of a branch, X 20. The obliquely directed rimule spiranien and the oral avicu- 



laria are quite visible. One ovicelled zooecium is shown near the top. 



6. A branch, X 20, with three ovicelled zooecia in the center. The rimule spiramen on 



the ordinary zooecia is well developed. 



7. Interior of zooecia, X 20, showing the proximal spine of the apertura. The large 



trau.sverse opening is that of an ovicelled zooecium. 

 S. Tangential thin section through the tremocyst, X 20. 

 9. A single zooecium of the same. X 100. In the middle of the figure a portion of 



the olocyst is visible. 



10. Longitudinal section through a zoarium. X 20. including both an ovicelled and an 



ordinary zooecium. 

 ap, apertura ; ol. olocyst: or. ovicell : «, septula : ti; tremocyst : tii. tuli\iles. 

 Middle Jacksonian (Castle Hayne limestone) : Wilmington, North Carolina. 

 Cat. No. 64121, U.S.N.M. 

 Figs. 11-17. Ochetosella roivsla, new species (p. 4.5.3). 



11. A group of the free, cylindrical zoaria, natural size. 



12, 13. Two branching fragments, X 6. The first specimen shows .m inversion of zooecia. 



14. A branched fragment, X 20. 



15. An example, X 20, showing the simple, round, oral avieularium. 

 16. 17. Two specimens. X 20, illustrating variations in the species. 



Jliddle Jacksonian (Castle Hayne limestone) : Wilmington, North ('arolina. 

 Cat. No. 04122, tT.S.N.M. 

 5S 



