PLATE 7. 



CoLUMNARiA STELLATA, Hudson Rivev Group. 



1. Vertical section of a corallum found in Trimble county. Collection 



of the author. 



CoLUMNARIA ALVEOLATA. HudsOfl BiveV Gvoup. 



2. Longitudinal section of a corallum found near Fisherville, Jefferson 



county. Collection of the author. 



