It is therefore plain that a marked change had gone on here and locally the facts may be interpreted two ways. First, that Orbeian Time began with deepened oratus, opening new sea ways with the immigration of a new fauna, the Richmondian fauna. Second that in Old Autunm Time the sea drawn back going into land conditions, and in Orbeian Time there was a re-invasion of the sea. From local conditions I prefer to adopt the former view and to hold that here in the Ohio Valley the Chesapilean sea continued throughout the Richmondian time.