PLATE 133— Continued. 



30. Anterior view of a large corallum. Collection of Mr. Nettelroth. 



31. View of the calyx of a corallum. Collection of the author. 

 From the ferruginous clay of the Lower Devonian, near Louisville. 



Zaphrentis ctngula. Devonian. 



32. Posterior view of a corallum, from the Lower Devonian rocks, 



Falls of the Ohio. 



33. Left lateral view of a corallum, from the same place. 



34. Anterior view of a slender corallum of unusual altitude, with lami- 



nated structure obscured by the deposition of silica in annular 

 dots during fossilization; from the ferruginous clay of the Lower 

 Devonian, near Louisville. 



35. View of the calyx of a corallum, from the horizon and neighbor- 



hood of the preceding specimen. 

 Collection of the author. 



