DEVONIAN FOSSILS 



77 



In Coenites ( Cladopora in older publications) the cups are 

 close together (see Trachypora above ). Some of the species 

 have stick-like, branching colonies, others are leaf-like and 

 flat. Several species of Coenites are found in our Devonian 

 rocks. 



Hexagonaria ( Prismatophyllum and Stylastraea in older 

 publications) is a large coral whose surface suggests a honey- 

 comb (fig. 153) with very large cells (as much as 3/8 inch in 

 diameter). H. prisma is the common species of the Columbus 

 limestone. 



The Devonian species of Favosites (fig. 154) are very sim- 

 ilar to the Silurian forms (fig. 84). In Devonian collections the 

 genus can be distinguished from Hexagonaria and its relatives Fig. 152 



by the smaller size of the tubes in Favosites. See also the next 

 genus, Emmons ia , for forms very similar to Favosites. The 

 genus is represented by several species in our Devonian rocks. 



In Emmonsia the tubes are usually more irregular in size 

 than in Favosites. This character is not constant enough to be 

 reliable in all cases but it is helpful in separating the genera. 

 Five species have been recorded from the Columbus limestone 

 and one from the Silica formation. 



The next four genera 

 are generally similar but 

 can be separated by 

 the characters given 

 in the key (nos. 7-9). 

 Eridophyllum (fig. 

 155) is found in the 

 Columbus limestone. 



Fig. 153 



Fig. 157 



Cylindrophyllum is much like Erido- 

 phyllum but the edges of the cups are not 

 joined together. C. propinquum (fig. 156) 

 is found in the Columbus limestone and C. 

 panicum in the Tenmile Creek dolomite. 

 \ 



Syringopora (fig. 157) and Synapto- 



phyllum are very similar except for size; 



Syringopora looks like a miniature 

 of Synaptophyllum. Several spe- 

 cies of Syringopora have been 

 found in the Columbus limestone, 

 the Olentangy shale, the Prout 

 limestone, and the Silica forma- 

 tion. 



Synaptophyllum (see under 

 Syringopora for characteristics) 



is represented by one species, J5. simcoense (fig. 158)of 

 the Columbus limestone. 



Hadrophyllum d'orbignyi , the button coral (fig. 159) 

 cannot be mistaken for any other coral. In fact, it looks 

 so unlike other corals that its nature may be in doubt Fi s- 159 



when it is first collected. The distinct septa on the up- 

 per surface will reveal its true relationships. It is rarely found in the Columbus and is abundant 

 in some beds of the Delaware. 



Fig. 156 



Fig. 158 



