The next younger beds of early to early middle Oxfordian Age in Alaska are characterized by Cardioceras sensu strictu and its subgenus Scoticardioceras. Of them, Cardioceras sensu strictu in Europe ranges through the Cardioceras cordatum zone and the lower part of the next younger Perisphinctes plicatilis zone. Scoticardioceras ranges through the upper third of the Cardioceras cordatum zone and all of the Perisphinctes plicatilis zone (fig. 12). Theoverlap of the ranges of these taxa is apparently reflected in Alaska by the association of Cardioceras sensu strictu with Cardioceras (Scarburgiceras) martini Reeside at three localities west of Cook Inlet (USGS Mesozoic locs. 3041 float, 11017, 21351) and at five localities in the Talkeetna Mountains (USGS Mesozoic locs. 24165, 24166, 24168, 24837, 24841). (from Imlay, 1981, p. 20);