PLATE 17. 



Favosites amplissimus, Nov. Spec. Devonian. 



1. Upper surface of a corallum from the ferruginous clay of the Lower 



Devonian, near Louisville. Collection of Mr. Nettelroth. 



2. View of a portion of the under surface of a corallum from the Lower 



Devonian, Falls of the Ohio. Collection of the author. 



3. Upper surface of a corallum from the Lower Devonian, Falls of the 



Ohio. Collection of the author. 



