154 NORTH AMERICAN INDEX FOSSILS. 



Coal Measures of Nebraska, Kansas, Missouri, Iowa, Illinois, 

 and Ohio. Rather common. 



LXX. Cceloconus Ulrich. 

 Simple hollow expansions from an attenuated striated base ; 

 zocecia short, with well developed hemisepta, and apertures in 

 diagonally intersecting series. Miss. 



Fig. 208. a, Nematopora ova/is, X Y an d X 9 > ^> Rhombopora tenuirama, X Yz and 

 X 6 and 12 (£', b ,f ) ; c, Coeloconus granosus, X Y an( ^ X 6 ; d, Bactropora simplex, X 

 l / 2 and X ^ ; «?, Streblolrypa nicklesi, X Y an <3 surface and section, X 9 '■>/■> Escharopora 

 subrecta, basal portion, X AY > g-> Arthropora simplex, X Y> an ^ surface X 9> an d 

 X !8; ^> Stictoporella cribrosa, X /^> an d portion X 9 > *i Rhinidictya mutabilis, X 

 ^ and X AY '■> Jt Phyllodictya varia, \Y (J )» surface X AY (/ )> anc * P or tio n X 

 9(/'). (All after Ulrich.) 



123. C. granosus Ulrich. (Fig. 208, c.) Mississippian. 



Lined on inside with thick epitheca ; apertures oval to subcir- 

 cular, the interspaces with granules ; basal portion with vertical 

 granulose ridges between the oval apertures. 



Chester of Illinois. 



