Plate LX Continued. 



PAQB 

 Fig. 6. POLYPOBA COMPLANATA Ulr 597 



6. Obverse face of a nearly perfect frond, showing base, extremely wide 



dissepiments, and the small fenestrules. Natural size. 

 6 a. Surface of same, x9, showing cells in different states of preservation, 



and che relative size of branches, fenestrules, and dissepiments. 

 6 6. Transverse section, x!8, showing flatness of obverse side of branches. 



6 c. Vertical section of a branch, x!8, showing strong inferior hemisepta, and 



form of zooecia. 



Chester group, Chester, 111. 



Illinois State Museum. 



Pig. 7. POLYPOBA CESTEIENSIS Ulr. (See also PI. LV) 594 



7. Natural size view of specimen from near Anna, Union Co., 111. 



Illinois State Musecm. 



7 a. Upper extremity of same, x9, showing appearance of perfect young 



examples. 

 7 6. Natural size view of specimen from Sloan's Valley, Ky. 



E. O. Ulrich's collection. 

 7 c. Surface of same, x9, showing appearance of branches near base of 



fronds. 



Fig. 8. POLYPOBA TUBEBCULATA PrOUt 595 



Obverse surface, x9, of a worn example of this species. More perfect 



specimens since examined show that the tubercles are more numerous 



and stronger, and the zooacia apertures with peristomes as at the lower 



end of flg. la. 



Chester group, Chester, 111. 



Illinois State Museum. 



