Plate 73. 



Fig. 1. Perigmtrclla clcijana, new .speoies (p. 57!_i). 



Tlie iucrustiug zoarium, X 20, illustmting the small zooecia aiul the unnierous rows 



of areolae. 

 Middle Jacksouian : Baldock, Barnwell Connty, South Carolina. , 



Cat. No. 64197, U.S.N.M. 

 Figs. 2-4. Pcrifiastrellu oioidea Canu and Ba.ssler, 1!I17 (p. oSO). 



2. Ance.strular portion of the incrnsting zoarium, X 20. The zooecia are quite convex 

 and the areolae are not visible. 



3. Another zoarium, X 20, showing the ancestrula. A salient nuiero is developed, 



hiding the apertura more or less. 



4. Interior of zooecia, X 20. 



Upper Jacksouian (Ocala limestone) : 1* miles above Baiubridge, Georgia. 

 Cat. No. 62613, U.S.N.M. 

 Figs. 5-7. Pcrigastrclhi maxilla, new .species (p. 580). 



5. The iucrustiug zoarium, X 20. The mugro is erect. 

 Middle Jacksouian : Rich Hill, Crawford County, Georgia. 



Cat. No. 6419S, U.S.N.M. 



6. Zooecia, X 20, in which the areolar pores are visible. 



7. Ovicelled and ordinary zooecia, X 20. The orifice of the ovicell is quite visible. 



The peristome bears eight spines. 

 Middle Jacksouian : IS miles west of Wrightsville, Georgia. 

 Cat. No. 64199, U.S.N.M. 

 Figs. S, 9. Perigastrella trapezoidca, new species (p. fi^^H. 



S. Ancestrular portion of the iucrustiug zoarium, X 20. The zooecia are almost 



smooth ; six to eight spines occur on the peristome. 

 9. Ovicelled and ordinary zooecia, X 20. Tne orifice of the ovicell is plainly marked. 

 Middle Jacksonian : Near Lenuds Ferry, South Carolina. 

 Cat. No. 64200, U.S.N.M. 

 Figs. 10-13. Pcrigafitrclla clcpressa. new species (p. 582). 



10. Ovicelled zooecia of this incrusting species, X 20. The apertura is shown as a 



slit while the orifice of the ovicell is not visiljle. 



11. Ovicelled and ordinary zooecia, X 20. Four spines occur on the latter and six 



on the former. No mucro is developed. 



12. A zoarium, X 20, showing the ovicell attached to the distal zooecium. 



13. Interior of zooecia, X 20. 



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

 Cat. No. 64201. U.S.N.M. 

 Figs. 14-19. Perigastrella rcclilincata, new species (p. 582). 



14. Interior of ovicelled zooecia, X 20. 



15. Sketch of apertura, X 70. 



16. Ordinary and ovicelled zooecia, .X 20. 



17. Portion of the incrusting zoarium, X 20, exhibiting the labial nuicro quite clearly. 



IS. Tangential thin section of a zooecium, X 100. The olocystal elements are arranged 

 in lines radiating from the mucro. 

 Middle Jacksouian (Castle Hayue limestone) : Wilmington, North Carolina. 

 Cat. No. 64202, U.S.N.M. 

 19. Area of ancestrula, X 20. The ancestrula js at the lower corner. 



A'icksburgiau (Marianna limestone) : Salt Mountain, 5 miles south of Jackson, 

 Alabama. 



Cat. No. 04203, U.S.N.M. 

 74 



