PLATE II. 



PAGE, 



Figs. 1-5. Styi,astrea Anna Whitf 420 



1. View of the upper surface of a specimen showing" the center of the cells occupied 



by the transverse tabulae 



2. Longitudinal section showing the external surface of the cell-walls striated by the 



rays. 



3. Enlarged transverse section of a single cell to show the vertical interadial ridges 



extending irom the sides of the rays. The central portion also shows the tab- 

 ular plate. i 



4. Vertical section of a part of a large mass, showing the tabular and also the side 



of the vertical rays with vertical ridges and intermediate cystose structure. 



5. Transverse section of several cells, natural size, and showing the transverse 



tabulae. 



Fig. 6. Rhynchoneixa raricosta Whitf. 421 



6. View of the ventral valve of the specimen described. 



Figs. 7-9. Streptorhynchus fxabeixum Whitf. 421 



7. View of a ventral valve. ' 



8. View of the dorsal valve. 



9. Cardinal view of the specimen fig. 7, enlarged to two diameters. 



Fig. 10. Receptaculites Devonicus Whitf. 419 



10. View ot the specimen described. 



