Plate LXI Continued. 



PAGE. 



Pig. 8. POLYPOBA CBASSA Ulr. (provisional) 60S 



8. Natural size view of the only specimen seen. 



8 a. Surface of same, x9. The zocecia apertures are obscured in part by 



abrasion and by a dense cortical deposit. 



Upper Coal Measures, Sugar Creek, Saugamon Co., 111. 



Illinois State Museum. 



Fig. 9. POLYPOBA NODOOABINATA Ulr tiOl 



9. Obverse surface, x9, of a well preserved example. 



9 a. Obverse side of another portion of same, x9, where the specimen seems 



to have suffered from abrasion. 



Upper Coal Measures, Crooked Creek, near C'entralla, 111. 



Illinois State Museum. 



Pig. 10. POLYPOBA GBACILIS Prout 599 



10. Natural size view of an example of this species. The tubercles are 



drawn a little too strong. 

 Keokuk group. 

 Illinois State Museum. 



10 a. Obverse surface, x9, of a well preserved fragment from King's Moun- 



tain, Ky., which shows no tubercles. 

 E. 0. Ulrioh's collection. 







