Vertipecten fucanus / Miocene / Clallam Formation |
These were collected on the foreshore near Clallam Bay, Olympic Peninsula, northwestern Washington.
Until Addicott's study from 1976, the area was considered middle Miocene. The new lower Miocene designation can be credited in large part to the restricted stratigraphic range of Vertipecten fucanus (Dall) and the restricted and overlapping ranges of several other mollusks.