PLATE V. 



Page 



Figs. 1 to 10. Phyllopobina corticosa Ulr -^ 21; 



1. A frond of this species exposing the poriferous or obverse side; natural size. 



2 and 6. Eeverse side of a fragment, natural size and a portion ¥9. 



3 and 7. Ohverse side of another fragment, natural size and a portion '=9. 



4 and 5. Two specimens of the basal portion of the zoarium, natural size. "^ 



8. Tangential section, xi8, cutting the zooecial tubes at varying depths from the surface. 



9. Transverse section of several branches, xi5. 



10. V-ertical section of a branch, xi8. 



Upper third of the Trenton shales, near Cannon Falls, Minn. 



•Figs 11 and 12. Rhinidictta grandis, n. sp 33 



A flneexamplefrom the -'Lower Blue" limestone at Dixon 111 ., natural size and a portion 

 X9. (See also Plate VI.) 



Figs. 13 to 18. Ehinidictya minima Ulr 13 



13. Three fragments of the natural size. 



14 and 15. Oue of them xQ, and a portion of same xi8, showing the small zocBcial apertures 

 and grano-striate character of the interspaces. 



17. Tangential section of the variety modesta, xi8, showing the appearences of the zocecia 



at various depths beneath the surface. 



18. Tangential section of the typical form of the species, xi8. 

 Upper part of the Galena shales, near Cannon Falls, Minn. 



Figs. 19 to 21. Ehinidictta paupera Ulr 12 



19. A nearly complete specimen, natural size. 

 20 and 21. A fragment, natural size xg and xi8. 



Upper third of the Trenton shales, St. Paul, Minn. 



Figs. 22 to 25. Ehinidictta NEGiiECTA n . sp 13 



22. A fragment of the natural size and a portion xi8, showing the usual characters of the 



species. 

 23, 24 and 25. Respectively, trarsverse, vertical, and tangential sections of a specimen wider 

 than the original of flg. 22, but agreeing in all other respects with it. 

 Trenton limestone near Danville, Ky. 



