The Collingwood maybe 30 feet thick and consists of zones of grey to dark limestones with intercalated Haech shale, replete with Oozites Canadensis, Delmanella, Plectrthis plicatula (very rare). Over the last is the Haech Utica Shales with T. Heceri, T. spinosus, Orthreues potter- forme, Leptothrix lepi, Jahirocarania filosa, small Pleurona, Cleurodonta and grapholitha. The question is are these dark beds Utica or Trenton. Raymond insists they are Utica while Ulrich is inclined to place them in the Trenton. His main conclusion for this conclusion is that the central bed at the bottom of the Presbbyra zone is the equivalent of the Curbsville Ky. Locality. In this third belief is wrong for there is another central zone here of Ottawa much lower down.