0EISKANY FAUNA OF BECEAFT MOUNTAIN 71 



Rhipidomella oblata H. — idem, Helderbergian, N. Y. 



Crania pulchella H. & C. — idem, Helderbergian, N. Y. 



C. cf. bella Bill. — idem, Gaspe limestone no. 5. 



Pholidops terminalis H.— idem, ? Oriskany, Md. N. Y. 



Ph. sp% 



Lingula cf. rectilatera II. — idem, Helderbergian, N. Y. 



llhombipora rhonibifera II. — idem, Helderbergian, N. Y, 



Stictopora sj). 



Unitrypa lata II. — idem, Onondaga limestone, Ontario 



U. acclivis II. — idem, Onondaga limestone, Ontario 



Lichenalia cf. crassa II. — idem, Helderbergian, N. Y. 



Polypora separata //. (?) — idem, Onondaga limestone, Ontario 



Polypora 



Polypora of. compressa //. — idem, Helderbergian, N. Y. 



Fenestella biseriata II. (?) — idem, Onondaga limestone, Ontario 



Hemitrypa columellata II. — idem, Onondaga limestone, Ontario 



Isotrypa 



Reteporina 



Edriocrinus l)ecraftensis C. — E. saeculus II, Oriskany, Md 



Ptyehonema heklerbergiae II (?). — idem, Helderbergian, N. Y. 



Vermipora streptocoelia C. 



Vermipora serpuloides //. var idem, Helderbergian, N. Y. 



Cladopora smicra 6".— idem, Onondaga limestone, N. Y. 



C. styphelia C. 



Anlopora cf. schoharie II. — idem, Helderbergian, N. Y. 



Monotrypella arbuscnlus II. db S. — idem, Helderbergian, N. Y. 



Hederella magna II. — idem, Hamilton shales, N. Y. 



H. arachnoides C. • 



H. ramea U. 



H. gracilior C. 



We may briefly summarize this tabulation as follows. Of the 94 

 clearly defined species of this fauna, 38 represent expressions of species 

 which began their existence in Helderbergian times; on the other 

 hand, but 18 of the species of the fauna continued their existence or 

 appear to be represented by closely allied forms beyond the close of 

 the Oriskany sedimentation. 29 are represented in the earlier known 

 fauna of the arenaceous beds of the Oriskany. 



