POLYZOANS. 15 



Stenopora emanciata ULRICH. 



Stenopora emanciata Ulrich, 1890: Geol. Sur. Illinois, vol. VIII, p. 438, 

 pi. Ixxiv, figs. 2-2a. 



Horizon and localities. Lower Carboniferous, Keokuk 

 limestone : Warsaw ( Illinois ). 



Stenopora intercalaris ULRICH. 



Stenopora intercalaris Ulrich, 1890: Geol. Sur. Illinois, vol. VIII, p. 439, 

 pi. Ixxiv, figs. 5-5a. 



Horizon and localities. Lower Carboniferous, Keokuk 

 limestone : Warsaw ( Illinois ). 



Stenopora angularis ULRICH. 



Stenopora angularis Ulrich, 1890: Geol. Sur. Illinois, vol. VIII, p. 439, pi. 

 Ixxiv, figs. 6-6b. 



Horizon and localities. Lower Carboniferous, Keokuk 

 limestone: LaGrange. 



Stenopora inter mittens ULRICH. 



Stenopora intermittens Ulrich, 1890: Geol. Sur. Illinois, vol. VIII, p. 440, 

 figs. 16a-b. 



Horizon and localities. Lower Carboniferous, Keokuk 

 limestone : Warsaw ( Illinois). 



Stenopora tuberculata (PROUT). 



Flustra tuberculata Prout, 1859: Trans. St. Louis Acid. Sci., vol. I, p. 



447, pi. xvii, figs. 3-3d. 

 Cydopora polymorpha ? Prout, 1860: Trans. St. Louis Acad. Sci., vol. I, 



p. 578. 

 Cydopora polymorpha Prout, 1866: Geol. Sur. Illinois, vol. II, p. 421, pi. 



xxi, figs. 5-5b. 

 Stenopora tuberculata Ulrich, 1890: Geol. Sur. Illinois, vol. VIII, p. 441, 



figs. 17a-b. 



Zoarium variable in size and shape, forming thin expan- 

 sions on shells of brachiopods and the hard parts of other 

 organisms ; often free, with a well-defined and wrinkled epitheca 

 on the under side. Surface nearly smooth. Zooscial openings 

 sub-circular or rounded polygonal ; tubes prostrate at first, 

 but rapidly curving outward; walls thin. Mesopores not 

 abundant; diaphragms numerous. Acanthopores of medium 

 size. 



