PLATE LXXII. 



PAGE. 



Fig. I. STREBLOTBYPA MAJOB Ulr. (See also PL LXXI.) 666 



1. Transverse section, x!8. 



1 a. Vertical section of small example, x!8. It divides the zoarium a little 



obliquely. 



Fig. 2. STBEBLOTBYPA EADIALIS Ulr 667 



2. Surface of a branch of the usual size and appearance, x!2, showing the 



minute pores in the posterior half of the hexagonal sloping areas. 



2 a. Tangential section, x28. showing structure just beneath the surface. 



2 6. Vertical section, x28, showing the small inferior hemisepta and other 

 features of the species. 



2 e. Deep tangential section, x28. Along the middle of the figure, the strong 



transverse lines or denticles represent the hemisepta, the dimly shaded 

 spaces, with which they alternate, the zooacia walls cut obliquely. 

 Keokuk group, near Nauvoo, 111. 

 Illinois State Museum. 



Fig. 3. COELOCONUS GBANOSUS Ulr 665 



3. A complete but compressed specimen, natural size. 



Chester group, near Anna, 111. 

 Illinois State Mueum. 



3 a. Another, less complete, natural size and x!2. 



3 6. Vertical section, x!8. 



Fig. 4. CoELOCOJfus BHOMBICUS Ulr 664 



4. Two examples of the natural size, with the lower two-thirds of one x!2. 



4 a. Vertical section, x!8, showing much thinner walls and epitheca than 



C. granosus. 



4 6. Transverse section, x>8. 

 4 c. Tangential section, xl8. 



Fig. 5. ANISOTBYPA SYMMETBICA Ulr 448 



An example of this species, natural size, showing arrangement of 

 zooecia apertures and the isolated large cells. 

 Chester group, Sloan's Valley, Ky. 

 E, O. Ulrich's collection. 



