PLATE LX. 



PAGE 



Figs. 1 and 2. INIembranipora rimulata n. sp 211 



1. Surface of' a specimen of the small-celled variety of this species. 



Upper Marlboi-o. X 20 



2. Surface of the type specimen. X 20 



Figs. 3 and 4. MEiiBRANiPOEA spiculosa. n. sp 212 



3. Surface of a specimen, showing form and arrangement of zooecia 



and ovicells. Upper Marlboro. X 20 



4. Several zooecia of same, more highly magTiified, 



Figs. 5 and 6. Membbanipora angusta n. sp 213 



5. Surface of a si^ecimen, shoAving connecting j)ores and ovicells. 



Upper Marlboro. X 25 



6. Portion of another and more worn specimen, without ovicells. 



X 20 



Fig. 7. Biplustba torta Gabb and Horn 214 



7. Portion of a fragment of the bifoliate zoarium of this species. 



Upper Marlboro. X 20 



Fig's. 8 and 9. Eeptoflusteella heteropora Gabb and Horn 213 



8. Surface of the Eocene form. Upper Marlboro. X 20 



9. One zooecium of same more hig'hlj^ magnified. 



Figs. 10 and 11. Eschara ?? digitata Morton 216 



10. Surface of a fragment of the Eocene form of this species. Upj)er 



jNIarlboro. X 20 



11. Perfect zooecium of same more highly magnified to show the 



lunarium-like process of the lower border of the aperture. 



Figs. 12 and 13. Ceibrilina modesta n. sp 218 



12. Portion of the tyiDe specimen of this species. Upper Marlboro. 



X 20 



13. One zooecium of same more highly magnified. 



Fig. 14. Cribrilina cbassula n. sp 218 



14. Portion of the somewhat worn sjiecimen described. Upper Marl- 



boro. X 20 



Figs. 15 and 16. Lepralia labiosa n. sp 220 



15. Surface of an average specimen. X 20 



16. Two young zooecia, each with two avicularia and a semilunate 



area in the upper portion of the apertural rim. X 20 



Figs. 17 and 18. Mucronella aspera n. sp 221 



17. Surface of a specimen. Upper Marlboro. X 20 



18. A few zooecia of another specimen. X 20 



Figs. 19 and 20. Ltjnulites reversa n. sp 217 



19. Portion of front surface of the specimen described. 2 miles 



below Potomac Creek. X 25 



20. I'orliou of dorsal surface of same. X 20 



313 



